To "Claim Your Home" and start using HomeManager, you want to go to landing.homemanager.io and click the "Claim an Address" button located in the top right of the web page.

You will then need to insert information about the address you are wanting to associate with your account.

If your address is already claimed, you will be prompted to contact HomeManager. In this scenario, you will need to provide some sort of evidence that you are the owner  of the address, and HomeManager will free up that address.