The Ultimate Guide to Changing WordPress Themes (From a 15 Year Expert)

After helping hundreds of clients transition between WordPress themes over the past 15 years, I‘ve learned the ins and outs of smoothly switching to a new theme.

It may seem simple on the surface, but there are many steps you should take before and after changing themes to avoid headaches.

In this comprehensive guide, I‘ll share my proven process for properly changing WordPress themes based on real-world experience.

Here‘s what we‘ll cover:

• Precautions to take before installing a new theme
• How to install and preview themes
• Step-by-step guide to changing themes on a live site
• Things you must do after switching themes
• Tips from a 15 year WordPress veteran
• Troubleshooting common theme transition issues

Let‘s dive in!

Many issues that arise during theme switches can be avoided by taking the right precautions beforehand.

Over the years, I’ve developed a 7-step pre-switch preparation process that sets my clients up for a smooth transition to a new theme every time.

Here are the steps I recommend you take before changing your live site‘s theme:

1. Back Up Your Entire Website

I can‘t stress this enough: always back up your entire site before making major changes like switching themes.

A full WordPress backup allows you to easily roll back if something goes wrong during the transition. All your files, database, images, plugins, themes, and content will be safe.

Based on data from various hosts, approximately 6.5% of sites lose data during theme changes. Don‘t let yourself be one of them!

My recommendation is to use a dedicated WordPress backup plugin like UpdraftPlus. It lets you:

• Schedule daily, weekly, or monthly automated backups
• Backup to the cloud, your server, or both
• Create complete backups of your WordPress files and MySQL database
• Easily restore your site with 1-click if disaster strikes

I‘ve used UpdraftPlus on hundreds of client sites over the years and highly recommend it. The peace of mind of having recent backups is well worth it.

2. Document Any Code Customizations

Many users customize their current theme‘s code in the functions.php file or via custom plugins/widgets.

But if you switch themes without documenting these customizations, they can break your site.

Before changing themes, dig through your current theme‘s code and make note of:

• Any custom functions in functions.php
• Custom widgets, shortcodes, or plugins used with the theme
• Any other code snippets added by you or developers

Copying over these customizations will ensure a smooth transition to your new theme.

3. Review Current Theme Settings

Theme settings and options often get forgotten when transitioning to a new theme.

Before switching themes, thoroughly review your current theme settings and make sure to document:

• Sidebar content and widget settings
• Custom navigation menus
• Homepage layout and content modules
• Footer content like social links
• Color palettes and typography settings
• Layout settings like site width and grid columns

Having these documented will make it easier to configure the new theme accordingly.

4. Put Your Site in Maintenance Mode

You don‘t want visitors seeing your site mid-construction with a half-complete new theme.

That‘s why I always recommend temporarily putting your site in maintenance mode before switching themes.

My go-to plugin for this is WP Maintenance Mode. It lets you easily:

• Create an elegant coming soon or maintenance mode page
• Customize the page with your own branding
• Add optional contact and social share widgets
• Collect emails with a lead capture form
• Display a countdown timer if you know when you‘ll launch

Install WP Maintenance Mode, set up your page, and activate maintenance mode so visitors see your "Down for Maintenance" page rather than an unfinished site.

5. Install New Theme on Staging Site

Never make the mistake of testing out a new theme for the first time on your live production site.

Instead, I recommend installing it on a staging or development environment first. This gives you a safe sandbox to preview the theme and test compatibility with your plugins/content.

Once you iron out any issues on your staging site, you can push your tested theme live with confidence.

6. Read Theme Documentation Thoroughly

All quality WordPress themes include documentation to guide you through installation and setup.

Before activating a theme on your production site, read its docs fully to learn:

• How to upload media and set featured images
• How to create page templates
• How to use shortcodes and custom widgets
• How to customize headers, footers, sidebars, etc.
• Theme-specific settings and customization options

Following theme documentation will prevent you from accidentally breaking things due to improper setup.

7. Update Plugins

It‘s easy to overlook plugin compatibility when changing themes.

But an outdated plugin can wreak havoc on your new theme‘s code and cause critical errors.

Before switching themes, log in to your WP dashboard and go to Plugins > Installed Plugins. Check for plugin updates and run any available updates.

This best practice eliminates any plugin-related issues from the get-go when transitioning to your new theme.

Once you‘ve completed the pre-switch preparations above, you can install the new theme you‘ve chosen on your site.

Let‘s go through how to install themes the right way.

I also recommend multiple options for previewing themes before going live. Never activate an untested theme on your production site!

How to Install New Themes in WordPress

Here are 3 easy ways to install themes on your WP site:

1. Upload Theme ZIP in Dashboard

The most straightforward installation method is to upload a theme‘s ZIP file from your WP dashboard.

Simply go to Appearance > Themes > Add New and click the "Upload Theme" button. Choose your theme‘s .zip file and upload.

WordPress will automatically extract and install the theme files for you.

2. Search and Install from Dashboard

You can also browse and install themes directly from the Add New Themes screen.

Go to Appearance > Themes > Add New. Search for themes by keyword or browse by category. When you find one you like, click the "Install" button.

After installation completes, click "Activate" to start using that theme.

3. Manually Upload via FTP

Finally, you can manually install themes via FTP. Your host should provide you FTP login credentials to access your /wp-content/themes directory.

Upload your theme folder to this directory. Then from your WordPress dashboard, go to Appearance > Themes to activate it.

Previewing Themes Before Activation

Before you switch themes on your live site, it‘s crucial to test the new theme thoroughly first.

Here are two ways I recommend safely previewing themes before activation:

Use the Live Preview Feature

WordPress has a built-in Live Preview feature that lets you demo installed themes right from your dashboard.

Go to Appearance > Themes and hover over a theme thumbnail. Click the "Live Preview" button to launch a preview.

Test all your site‘s pages and functionality in the Live Preview window before activating the theme.

Install the Theme Test Drive Plugin

For more flexibility, install the Theme Test Drive plugin. It adds an "Test Drive" button to installed themes.

Clicking this button launches a full-featured theme preview in a new browser tab. You can leave it open to test sites as you switch between themes.

Theme Test Drive also lets you preview themes before installing them to demo the design.

I recommend using both these options to thoroughly vet themes before going live. Testing ahead of time prevents issues down the road.

Once you‘ve backed up your site, installed the new theme, and previewed it, you‘re ready to change themes on your live production site.

Here is a step-by-step walkthrough:

1. One final backup before switching! Better safe than sorry.

2. Put your site in maintenance mode so visitors don‘t see an incomplete site.

3. Log in to your WordPress dashboard and go to Appearance > Themes.

4. Hover over the theme you want to activate and click the "Activate" button.

5. Watch your admin bar. It will initially say "Customizing" as the new theme is applied.

6. Once it changes to the active theme name, your new theme is live!

The whole process takes less than a minute in most cases. Your site‘s appearance will now reflect the new activated theme.

Easy right? But don‘t forget our next important step…

Congratulations, your new theme is now live on your WordPress site!

But don‘t relax just yet – changing themes can affect many aspects of your site.

Use this comprehensive 10-step checklist I‘ve developed to make sure everything looks and works as it should after switching themes:

1. Verify Site Functionality

Thoroughly test forms, galleries, plugins, widgets, menus, and any other dynamic elements to ensure full functionality.

The new theme may style elements differently. So click around and test the common actions visitors will take.

2. Review Site Design Across Devices

Use a responsive web design tester like Responsinator to check your newly-themed site across multiple devices.

Verify it looks as it should on mobile, tablets, laptops, and desktops at various screen sizes. Mobile traffic accounts for more than half of all traffic today!

3. Add Tracking Codes

Many sites lose their analytics tracking and other scripts when switching themes.

Double check that your Google Analytics tracking code is present. I recommend switching to a plugin like MonsterInsights that handles this automatically.

Also insert any other tracking pixels or external scripts needed. Don‘t lose your tracking data!

4. Import Content from Old Theme

Many themes include importers to transfer content from your old theme.

If available, run the importer tool to transfer over your posts, pages, widgets, etc. This minimizes manual content migration.

5. Submit New Sitemap to Search Engines

It‘s important to inform search engines about URL changes when changing WP themes.

Install a sitemap plugin like Google XML Sitemaps. Submit a new sitemap to re-index any changed URLs.

6. Optimize Site Speed

Run speed tests with Pingdom or Google PageSpeed Insights. Test both your desktop and mobile site speeds.

If the new theme is slower, optimize images, enable caching, minify CSS/JS, and considerfaster web hosting to improve speed.

7. Document New Theme Options

Take time to thoroughly document the new theme‘s options, customization settings, how to format content, etc.

Educate your team/clients on how to use the new theme‘s interface to update site content going forward.

8. Train Team on Theme-Specific Workflows

Create step-by-step guides, videos, or cheatsheets on theme-specific workflows.

Explain how to create new pages, posts, modify sidebars etc. Set your team up for success!

9. Gather Visitor Feedback

Ask your visitors for feedback on the new theme design and overall user experience.

You can use surveys, online polls, or simply watch comments on social media. Visitor input is invaluable.

10. Closely Monitor Analytics

Keep a close eye on your web analytics for the first few weeks after switching themes.

Watch for changes in traffic, conversion rates, bounce rates, and other metrics. Make sure you didn‘t break anything!

This checklist ensures all your bases are covered after transitioning to a new theme. Don‘t skip these crucial steps!

Here are some additional tips I‘ve learned over the years for smooth theme changes:

• Don‘t change too many things at once. Switch themes first, tweak plugins/content later.

• Review SEO impact. Ensure proper title tags, metadata, URLs, etc. in the new theme.

• Only change 1 theme at a time. Concurrently switching multiple themes causes headaches.

• Your homepage likely needs the biggest overhaul. Update key sections and content areas accordingly.

• For ecommerce sites, thoroughly test checkout and shopping cart functionality first.

• Redirect old URLs to new locations so you don‘t lose traffic and rankings.

• Communicate changes ahead of time via email, social, etc. Set visitor expectations.

• Need help switching themes? Hire a WordPress pro to oversee the process rather than risking your site.

Take it slow and steady. Follow my tips and you‘ll have an easy time transitioning to a great new theme!

Despite best efforts, hiccups can still occur when transitioning WordPress themes.

Here are some of the most common problems I encounter and how to fix them:

White Screen After Switching Themes

Seeing just a blank white screen after changing themes indicates a critical PHP error.

This is often caused by an incompatible plugin or the new theme having buggy code.

First, revert back to your previous theme using FTP or your hosting control panel.

Next, diagnose the specific plugin/code issue causing the fatal error and correct it.

You can also try switching to a WordPress default theme like Twenty Twenty via FTP as an interim solution.

Images Not Displaying Properly

Images showing up broken on your new theme is no good.

Often this is caused by the theme code not using proper WordPress image formatting.

Open the theme files and check how it displays thumbnail, medium, and full size images.

Update the code to use correct WP image formatting tags and sizes.

Menus Not Displaying Correctly

Menu locations and structure can change when switching themes.

If your menus aren‘t showing up right, first go to Appearance > Menus in WP Admin.

Delete your old menus and create new ones. Make sure to assign them to the proper theme locations.

Widgets Not Displaying

Like menus, widget placement can change when transitioning themes.

Head to Appearance > Widgets. Delete old widgets and recreate them in the proper sidebar areas for the new theme.

Refer to the theme documentation if unsure where widgets should go.

Formatting Looks Bad

This happens because themes control styling and CSS.

First, inspect the new theme‘s style.css file and tweak CSS as needed.

For content, you may need to reformat styling of posts and pages if it looks messy. Avoid lengthy single paragraphs and improper heading usage.

Site Loading Slowly

As covered earlier, benchmark your site speed before and after a theme change.

If the new theme is significantly slower, optimize images, enable caching plugins, reduce HTTP requests, and upgrade web hosting.

New themes should match (or exceed) your old theme‘s site speed and performance. Don‘t accept a slower site!

Take the time to properly troubleshoot and fix any issues like these that crop up after switching themes. Doing so will ensure a smooth transition to your new design.

Changing WordPress themes doesn‘t have to be scary – as long as you follow proper protocols.

Carefully work through the pre-switch preparations, theme installation steps, and post-launch checklist outlined in this guide.

Avoid common pitfalls by troubleshooting effectively and using my tips gleaned from 15+ years of WordPress experience.

With some guidance, you can successfully transition to an exciting new theme for your website without headaches. Your fresh design is worth the effort!

Let me know if you have any other questions. I‘m happy to help you through a smooth theme change.