You can start by going to Employee Self Service (ESS) to login with your UW Net ID and password. For new employees, the welcome page in ESS will have a link to start your direct deposit. Otherwise, you should see the Direct Deposit link toward the top of the screen.
If a paper form must be used, please go to the Forms section for the Direct Deposit Authorization Form. Once it's filled out with a voided check attached, please send it to the UW Payroll Office (campus mailbox 359555).