When you fly a loop you want to hear the stall horn, as you slow down while going up ease your pull while maintaining the stall horn, you can pull hard when you're inverted because gravity is helping you, as you descend you can pull harder to maintain the stall horn, if you get tunnel vision at the bottom of the loop and can't hear the stall horn you're too fast. You can use flaps at the top of the loop to get your nose over quicker.