This is a test of commonsense. Complete the next sentence:

How to do pull ups for beginners
Do flexed arm hangs.
To build muscles in your shoulders and arms, start with flexed arm hangs. To do flexed arm hangs, place a box near the pull up bar that puts your chin just over the bar.
Place your hands on the bar with your palms facing you. Lift yourself upward and hold yourself slightly over the bar.