I generally one arm deadhang like in the videos, so halfway between pronation and supination, shoulder square to the hold.
On back3, though, sometimes I want to fully supinate, so I have to basically have to put myself on the other side of the board and grab the hold with the palm facing myself; I do this because this position engages much more my pinky, which in the normal half/half position, due to its shorter length compared to ring finger, gets very little activation.
Anyway in my last session I added 2 kg to both left and right hand, half crimp. Now it's getting heavy, it worked my lats and arms quite heavily. Good session.