An Excerpt from
The True Art and Science of Hand Balancing
You can practice the press up by reversing–doing a hand balance against the wall and dipping and pressing back up, all the while resting the feet lightly against the wall.
Later, try it free, dropping the nose to the floor, then pressing back. This can be easy–or very difficult.
Drop almost vertically, touching the floor near the hands, and keeping the feet well forward, and it is much less difficult than if done in planche style, extending the head far out, and feet far back. Notice that the feet are a bit farther back, and the head much farther forward; also, the shoulders are considerably more in advance of the hands.
On all press-ups, the farther forward you carry the head, the less like a press-up and the more like a planche you make it; comparing it with lifting a barbell, a correct press-up is like pressing a bar in close to military style (or if you have considerable back bend, then it is like prone press) but doing it in planche style is like holding a heavy barbell with the bar at the front of the thighs, then with elbows straight raising it through a half-circle to overhead–some difference!