Adding a return-to-top button for Wordpress is really easy, and allows visitors to quickly get back to the navigation and important links at the top of your Wordpress site. Here's how to add one:

1. Log into your Wordpress dashboard.
2. If you don't already have one, install a custom JS/CSS code editor plugin.
   • Using a plugin, instead of editing the theme directly, is a better way of customizing your Wordpress header/footer in the long term.
   • Certain themes, like Divi, allow adding links to the header/footer without having to install a plugin, so you should check if this is possible.
   • If you're familiar with Wordpress widgets you can also add the code to the “Text” widget, so long as it displays on the pages you want the back-to-top button to appear.
3. Assuming you installed and activated the plugin linked above, click the Settings > Header and Footer link on the left-hand nav of your Wordpress dashboard.
4. Add your Back to Top Button code before the </BODY> closing tag, and click the “Save” button.

That's it! Now just make sure you've cleared your cache if you use one, and have enough content so when you scroll down you can see the return button appear.

Want to add a back to top button to your Tumblr blog? Learn how here.