Start by using this link to open UltraTime in another tab.
Use your MSU NetID (ie. doejan3) as your user ID and the temporary password, 4321
Once you've typed those both in, click on the button that says, "Change"
UltraTime will then prompt you to enter your previous (temporary) password, and then a new one. You'll be asked to confirm your new password by typing it a second time.