Question [Q] Google # and T-Mobile Number Question?

Friends,

I use google as my main phone number and forward it to my t-mobile number for incoming calls. To avoid confusions with changing phones, numbers I keep my google number static so that I don't need to let everyone know that I have a new number.

How can I make calls out using my google # so that people will always see that number and not t-mobile? At current, I block my t-mobile from caller id, but sometimes it can be hassle or make people nervous.

Any ideas would be appreciated.

Thank You,

tvos