Key Takeaways
The welcome screen has one button, Connect a broker account. Press it, confirm your Country of Residence, and press Am I eligible?

If Alpaca does not accept your country you see a Not Eligible dialog. In that case use Amal x Trading 212 instead.

Eligible users see the perks list and a Connect to Alpaca button.

Pressing it opens Alpaca in a new tab and shows a Keep this window open reminder in Amal.

On Alpaca's site, create the account with your details and identity document. This is Alpaca's own KYC process and Amal never sees the documents.
Return to the Amal tab. The reminder has become Welcome back with a Link my Alpaca account button. Press it, approve the connection on Alpaca's page, and you are sent back to Amal with a Connected! message.

After linking, Amal shows one of these until the account is active:

The Alpaca tab closed before I linked. Sign in to Amal again. Onboarding resumes at the linking step.
I already have an Alpaca account. You can link it. Press Connect to Alpaca and sign in to your existing account instead of creating one. Amal needs its own authorisation even for existing accounts.
Approval has taken more than a week. Email [email protected] with the email you used at Alpaca. We can check the status on our side.