I found this while quickly checking out another forum...I don't now of this site has been posted before on here.
http://www.transgendervoice.net/index.htmlI thought it might help those who don't know where to start with modifying their voice.
For MAAB trans people, the first things that will dramatically change your voice is eliminating chest resonance and avoiding lower pitches when speaking (basically an "effeminate male" sounding voice). The site goes into a bit of detail through exercises.
The site has a few tips for FAAB trans people too, not much for FAAB people, but basically the exercises are interchangeable.