This may not apply to you but sometimes people don't notice what the rotor disk is doing. It's a blur but you can see the angle of tilt. Since the disk is the thing doing the flying it's important to notice the tilt of it. If you're attentive to the tilt and get it level (except for the amount required to counter the tail rotor) then when the heli is stopped then it will stay put. If you don't notice the tilt then you won't know there is an error till the thing starts going somewhere. When making corrections try to stay in touch with the tilt of the disk, and keep the tilt small for small errors. Stay ahead of the game. If you're correcting the position, returning to a certain point, before you get back to that point level the disk before you get to that point and be prepared to tilt a little the opposite way to stop the motion, then level the disk as the heli comes to a stop. Fly the disk.