In Mailchimp:

In Mailchimp, select the audience you want to connect to. Then, in the menu panel, click Signup forms.

Click Embedded forms, then click the Unstyled tab (which removes all the styling junk we don’t need).

Scroll down to the “Copy/paste onto your site” section. Copy the HTML code and paste this HTML code into a plain text document on your computer (you can just paste it into something like Word, Apple Pages, a Google doc, etc.)

And you’re all done!