After doing 4-5 push-ups rotate 90 degrees on one foot while the other foot is resting on top. The key here is to make sure your core is tight. Mentally, imagine pulling your belly button to your spine.
There are four rotations to this exercise, 360/90 = 4 (yup, impressive, we know). Each rotation means 4-5 more push-ups. When you return to the 12 am/pm position (so that's why they call them clock push-ups!) you're done.
Can you please keep your butt down? Please? Back flat and butt down. Repeat after us… Or don't and just try not to do it.