DE question. Football. On keeping balance?

Use swim (basically a quick overhand swipe on his arms) and rip moves with your arms. I suggest watching some plays of good NFL lineman and take note on some of their moves. Granted dwight freeney's spin move may be above your skill level (as it is for about everyone). but u can learn good technique and moves by watching the best in the world do it. Hope this helps. O and for the first part, just hit the weight room and put on some more weight, as once you become bigger and more physical you wont be getting hit and thrown of balance nearly as easily. And just remember, low man wins