Ah I see what you mean now:

http://www.homelink.com/training/print.taf?i=gdo_bumper

Empty page here too, looks broken I'd send an email to the webmaster.

 

If you know where the programming button on the garage door motor is then the rest is easy. I did mine in the garage but make sure you car is clear of the garage door before you start.

First turn the ignition on - the Porsche is one of the few cars I've owned where Homelink isn't always powered on. Then follow the instructions as they are written in the Owner's manual. I had a problem once where the batteries in the remote were weak so make sure your remote unit has fresh batteries. Once all the ligths flash as per the maual and you push the Homelink button and nothing happens then you probably have the rolling code model of garage door opener. If that's the case, press the programming button on the garage door opener, then get back in the car. You usually have at least 30 seconds to do this. Once you're in the car with the ignition on again, push your Homelink button, then push it again and most likely on the third push your garage door will work. If this doesn't do it then I'm out of ideas. Good luck.

 

Here are the general instructions for a Porsche from Homelink:
http://www.homelink.com/training/train.taf?do=3