I was never taught (or shown) how to hold the handle when inverted so I simply did whatever felt natural and comfortable for me. The end result was that I lay my hand over palm up when inverted and it's now instinctive for me that when my hand is palm up then controls are reversed. I say do whatever feels right to you. Never concentrate and what your hand is doing during manoeuvres either, that's a recipe for disaster . A friend of mine once videoed me closeup doing square eights and I couldn't believe the hand/arm motions I make .