The new generation banks like HDFC, ICICI etc have proper forms that you can fill to transfer your account from one branch to another. However, the nationalized banks like SBI, SBT etc do not have any such documents readily available. In such cases, you can submit a request written or computer printed on white paper. You can address and hand over the letter to your original branch or the manager of the new branch. The transfer may take one or two days and you may get a confirmation call from the old branch.
See step by step instructions to transfer bank accounts to new location.
You can download a sample letter from here.