On WordPress, it’s easy to change themes for a website. Simply go to Appearance > Themes, and you can preview how your site might look in another theme.
Before you decide to switch to a different theme, there are some things you should keep in mind.
The Good News
Switching themes does not destroy any pages or content that you’ve created for your site. Moreover, switching themes is reversible; if you change it and don’t like it, you can switch back.
The Tricky Parts
When you switch themes, it’s possible for your top navigation menu to break. This can be fixed by going to Appearance > Menus, finding your Top Nav menu, and checking the ‘Primary Menu‘ checkbox.
Many themes have a custom homepage page template that may not exist in a new theme. For example, switching from Hale to Sherman may wipe out the homepage. However, the widgets that created those homepages aren’t gone. If you go to Appearance > Widgets and scroll down, you’ll see them in an area for ‘unassigned widgets‘. Drag them back up to the correct sidebars and your homepage will reform itself.
In the newer themes (Hale 2015 and Sherman), you can use Page Builder to build the homepage and sub pages. See Homepage Customization tools.
Some themes have sidebars that are specific to them and changing themes will move any widgets within those sidebars to the ‘unassigned widgets‘ section in Appearance > Widgets. You may need to find a new place to keep that content.
Bootstrap Layouts & Special Elements
The older Hale and Prudence themes were built on the Bootstrap 2 framework. The newer Sherman and Hale 2015 themes are built with the Bootstrap 3 framework. If your site makes use of Bootstrap columns, buttons, or accordion menus, they may not work if you switch from a Bootstrap 2 theme to a Bootstrap 3 theme. They will fall back to being simple single column layouts, links, or text sections until you change the code to comply with the version of Bootstrap that your new theme uses.