Most people do plyo wrong. Mainly, they forget that they need to absorb the shock on the landing. That's where many of the benefits come from. Plyometric push-ups activate the fast-twitch fibers in your chest, shoulders, and triceps.
To perform the depth plyo push-up, you're going to start from a higher position, land lower, then project yourself as forcefully as possibly.
Set up a couple of short boxes or stacks of plates. Make sure you have room to place your hands correctly in the landing position. Start with your hands on the plates.
Drop to the floor, catching yourself in a 90 degree elbow position. Immediately explode back the plates.
When you land on the plates, pause and reset on every rep.