Google Voice Help

Hi I need help setting up a Google voice number on this Droid 2 I for my sis. I have a Droid x and I have a completely different number for my Google voice the I can text and make calls from. I did mine from a computer ages ago. I don't have a computer here now so I was trying to do it from her phone but I'm so lost. Can someone plz help me figure this out

You still have to go through the web site to set up Google Voice. Without a PC, just use the phone's web browser @ www.google.com/voice

Thankyou so much