Follow the instructions in the getting started section located here:
https://support.shedesignsthings.com/start-here
You can also watch the video editing tutorial here
You may choose to connect your custom domain to your link-in-bio page or use the standard Google Site domain link. I recommend creating a subdomain so that you are able to track your link-in-bio traffic inside of your google analytics.
NOTE: You do not need a custom domain to track analytics. See the analytics guide for setup instructions.