I had a fairly deep voice before T. Some ways of lowering it are smoking (not recommended), drinking milk, and practicing singing low. Deliberately pitch your voice as low as you can when you talk without having it show in your face.
Also, watch the way you pronounce consonants, like S and T, that can give you away as feminine. A more masculine pronounciation will result if you move the tip of your tongue further back on your upper palate.
Otherwise, yeah, T is the best way to do it. And that is a blessing.
Dennis