You can't. Creating more than one account is also not allowed.
Unless you mess up during account creation.
Sketch has said that, while they don't really approve of people having more than one account, it would be acceptable if the other account were to be retired (ie used no longer). But then you lose everything that the first account has.
The team could also unlink your Passport account so that you are free to create a new one. This is only done in special cases, but you can request an unlink by e-mailing [email]bnetbugs@microsoft.com[/email] and explaining the problem to them.
[Edited on 7/20/2004 1:37:18 AM]