Well, what I did was just gradually raise my pitch over the course of a few years or so...I sort of did it before/right as I was hitting puberty, but it did me a lot of good. Oddly enough, I was actually emulating Chris Colfer on glee-who knew something good could actually come of that show? Once you get your pitch up there, focus on finding a more natural timbre-don't be nasal and don't be entirely chest-y either. Focus on using the uppermost range of your chest register, but don't stay only in the upper range. Focus on increasing the range you use when you speak. I found that I actually had to go down in pitch once I actually transitioned...that's all I can say. I've gotten great results without any professional help whatsoever-my voice passes for cis over the phone even with other trans* people, so I don't know if I was just lucky-but either way, best of luck to you.
