I can do this 100% of the time with a false turnover. It's a move where you pretend to turn a coin over onto the back of the other hand, but actually leave the same face facing up.
Just say "i'm going to flip the coin, catch it, and turn it over onto the other hand"
Then flip it, catch it, get a peek at which face is up, and either do a real or a fake turnover depending on what you need. I came across a
Coinstar machine while practicing and realized even spare change can be useful. You'll have slow reactions at first but after practice you can do it full speed.
MUCH easier and more reliable than trying to control the flip ....