Child Themes are important if you want to edit any of the code in your WordPress theme. Without them, any changes you make to the original theme in CSS or php will be overwritten by new updates.
Here is a step by step guide of how to install a WordPress Child Theme.
My theme is called Skacero Lite so I named my Child Theme skacero-child. You can call it anything. Just don’t use any capital letters or spaces as this might create problems on some computers.
Right click on the Child Theme folder to create a new file. Now, save the file by clicking Control+S. A pop up box will appear just like when you save any other file. Save it under the name style.css in the pop up like you would any other file.
Copy and paste this information into your new style.css file:
Theme Name: Skacero child theme
Theme URI: http://www.icynets.com/skacero-theme/
Description: Skacero Child Theme
Author URI: http://http://www.icynets.com/
/* =Theme customization starts here
Change the names to the name of your own theme. The most important thing is the Template and the @import lines. The rest you can just leave as it is.
Go to Appearance –> Themes and then find and download your Child Theme the same way you would download any other theme. Note that your Child Theme will first exist after you complete the above steps.
Any information in the style.css file of your Child Theme will now overwrite the information in your parent theme.
Why can’t I find the Child Theme in the theme store?
Child Themes don’t exist in the theme store like normal themes. To be able to download them, you first have to follow steps 1-3 in the step by step guide.
Another reason could be that you have written something wrong. Try changing the name of your Child Theme so that there are no spaces and no capital letters. Use the template: theme-child (using your own theme name). My Child Theme is for example called skacero-child.
Why can’t I just edit directly in the parent theme?
Every time your parent theme is updated, your changes will be overwritten, meaning that you would have to recreate all the custom-made code if you want to update! With a Child Theme, the updates will not overwrite the customized code.