Set up in a regular push up stance, but bring your hands across the center-line of your body to create an ‘X’ shape.
Slowly lower yourself to the ground, allowing your elbows to flare out to the side and create a parallel angle at the bottom of the rep.
Drive your hands into the ground to work your way back to the top of the rep. This will change the strength curve of a normal push up, engaging the forearms (a lot!), the triceps, the front delts and, of course, the chest.