In that other thread, about passing privilege, it was said that 80% of passing was voice, so I looked up a regime and started practicing right away, lol.
I thought that I sounded phony and awful, but I recorded it, and thought that it sounded a lot better in playback than in my head, and sounded somewhat like my sister at points.
I think that I'm more confident that I will be able to pull off a decent sounding voice, than a convincing look, lol. Hoping that voice makes all of the difference, and I'll put a lot of effort into that.