Pretty much like a golfswing. Bend knees to be able rotate your hips. But remain quite straight back. I think you get a better momentum gliding in to the shoot. Rising your stick - weight on backleg (and feel it up to bottom), Hitting - weight distribute to your front leg. It can help to have the ball couple of centimetre forward from your center. Be mad but not angry! Need explosive adrenalin but focus. Grasp the stick little harder! A bit like fist your hand ready to hit someone. Grasp higher up with both hands can help but also loose control. For backhand you could open up your shoulder by doing a more circle motion when rising the stick, otherwise the same.