A good visual my coach used was to have me hang on a bar (like a gymnastics bar) then get in my hollow body position. He goes, if you're staying this tight, how can you flip over the bar without bending? He told me to not pull my toes over the bar, or my knees over the bar, but my hips TO the bar. When you're in your layout, your primary source of the energy for your rotation comes from your hips. You never want your toes to be in front of your hips. But I'm NOT saying to try to whip it over. If you are in the correct position then your hips will be forward and the natural arch in your back will be completely flat. To get it like that you really really really have to squeeze your butt and abs to stay tight! So once you ate used to that position, when you're going for your layout, think: "ride, hips to the bar, FREEZE!" Once you get your hips to the bar, don't move!!!! Piking out of it at the end kills execution scores. But remember to practice your hip drive and really condition your abs! I hope I helped!