I'm mostly thumbs, but sometimes use my index fingers as well. When I fly with a strap, I don't connect the transmitter until I'm ready to taxi. When the transmitter isn't on the strap, the strap is down the front of my shirt.

One thing I haven't seen mentioned yet is adjusting the length of the sticks. Not all TXs have adjustable sticks, but it's one way to find a comfort zone. Play around with that and the stick tension to find what's right for you.