This question is asked a couple of times a week.
Approval times vary quite a bit, some accounts are approved almost immediately, while others get flagged for manual approval and can take a few days. I think this is (at least partly) because of DreamHost's internal fraud detection system.
Once your account is approved and functional, you can transfer your domain(s) over to DreamHost by changing the DNS settings on the domains to;
You can then use the Web Panel function to transfer the Domain(s) to DreamHost.
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