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

How to reverse swing a cricket ball
Pick a side of the ball to polish after 5 overs.
Choose one side of the ball to keep polished and shiny. Leave the other side of the ball alone so it develops wear and tear throughout the rest of the match.
If 1 side has visible wear on it after 5 overs, polish the opposite side. Gather sweat or saliva from your body.