Assuming you are doing all of this already but here is what I was taught by Chris Birch.
- Sit very far forward on the seat. If you think you are far enough forward you probably aren't.
-Butt cheek should be hanging off the side of the seat.
-Inside leg should be out and even with your front fork leg.
-Outside leg should be on the peg trying to break it off by pressing on it. There is no such thing as pushing too hard unless it actually snaps off.
-Head should be forward and positioned vertically above the contact point of the front tire on the ground looking up and forward.
-Hand placement and pressure is kinda hard to explain online.
If you ever get a chance to go to a local professional riding school even for just one day you'll be glad you did. Best money I ever spent on bikes was classes with Pro's.