➡️ Here is a quick VIDEO about this process.
First, go to your current registrar where your domain is currently hosted (ex. GoDaddy) and make sure your domain is unlocked. Then get a transfer/authorization code for the domain. If you don't see an option to get this code in an easy to find location, you can contact their support for assistance.
When you have that code:
If you DO have an existing domain.com account, simply login and click on the blue button in the top right corner that says "Transfer a Domain".