What they are
Settings → Self-signup links mints a link you can put on your site or send to a prospect. They complete intake themselves and land in your workspace.
If you have connected your own domain, the link uses your domain.
Turning one off
Deactivate the link in the same section. Existing clients are unaffected — deactivating only stops new signups through that link.
Compliance still applies
A self-signed-up client goes through exactly the same disclosure, contract, and cooling-off sequence. Self-signup saves typing, not steps.