The pitcher's mound sex position is a sexy seated position that sizzles with mutual coordination. To get into the position, the partner on the bottom needs to take a comfortable seat on a sturdy chair. The partner on top can then slide into place and use feet on the ground to find the most comfortable angle. A mutually coordinated lift/thrust action will allow playmates to maximize the effectiveness of this round. Emphasize the lift, and leave thrusting as the supporting act.
By using a chair that's fixed and very solid, you're going to be able to really let loose in this position and put all and any desired energy into sweating this one out. In lieu of that, both partners should try to maintain a solid footing.