This article goes through how to install StickyEmail Sign Up forms on a Square Space website. Note: this adds codes to your entire site.
To add the code to a single page on your Square Space Site click here for directions
DIRECTIONS TO FORMS TO EVERY PAGE ON YOUR SITE
1. Copy the form code (Slide out or Exit Pop Up) for your email sequence.
2. Open your Square Space Site Editor
3. Go to Settings -- Advanced -- Code Injection
4. Paste the copied code into the footer section.
You can add both codes to the same Footer Section. For details on more information you can read how to use Code Injection here: Squarespace Code Injection
5. Publish Changes to view on your website.
Added Exit-Pop Up with Slide-Out