I have been meditating for 2 months now in (indian style?) with legs crossed normally. I prefer to continue using this posture, maybe even dare full lotus after I find proper stretching exercises. However, right after 20 minutes, one of my feet and eventually both become completely numb. They often hurt as they 'wake'. I use a small hard pillow to sit on and a towel underneath my legs. Do you have any suggestions on improving blood flow in any way?