how do I startup my own bank?

Answer 1

May try this link;
http://www.startabank.com/

Answer 2

In the US? You can't. It's very strongly regulated.

However, there is a tax loophole (isn't there always? ;P) where you can set up what is called a "brass plate bank" in a foreign country (usually either the Bahamas or Burma). There are companies there that, for a fee, will "create" a bank for you that exists in what amounts to a PO box with a brass plate on it that state's the "bank's" name.

The purpose of these is usually to funnel money to avoid paying capital gains taxes.