Setting up Google Voice Voicemail on a T-Mobile phone

As with other things on this site, I'm lazy and hate to run into a problem that requries hours of digging through forum posts for a solution. The following is (probably) what you should do if:

If all of the above apply to you, the solution is fairly simple:
  1. In a browser, login to your Google Voice account, and click on Settings. In the Voicemail tab, set up your greeting.
  2. On your phone, install the Google Voice App.
  3. From your phone's dialer, enter * * 0 0 4 * [Your Google Voice Number] #

That's it, pretty simple.
To disable forwarding, again from your dialer, dial: # # 0 0 4 #

h o m e       |        b l o g       |        s o f t w a r e       |        t h i n g s