After receiving the Welcome email, the next step is to create a subaccount.
You can create a subaccount by going to the BTP Cockpit＞Account Explorer view＞Create (blue button from right side)＞Subaccount. Provide a display name and select the region/provider. The subdomain (URL) will automatically be populated for you based on the display name given.
Please consult the help documentation to see the region and provider options available for this service. It is important that you are diligent in this selection because choosing the wrong region and provider will result in you being unable to find the service in subsequent steps. For convenience, the help page is listed in this section.