I'm trying to sit way deep and push forward into "the wall"... I am squeezing w/ my inner thigh but then my lower leg slides forward so I try to move it back but then I end up squeezing with my calf and I think that's why I am slightly speedy... I can't figure out the sit back part, in english you kind of end up w/ a bit of an arch in your back, but I don't want that western right? I think I know what to do but I can't make my body do it... any tips?