FEEL: You should feel your glute and hip muscles working the most. You should also feel your core and shoulder muscles working.
COMPENSATION: Make sure you lift your hip off of the ground and rotate your knee up all in one motion.
FEEL: You should feel your glutes work to control this motion. At no point should you feel your low back muscles doing the lifting motion. If you feel it only in your hamstrings, try bending your knees a bit more and repeat.
COMPENSATION: Avoid arching at the low back as you perform this.