Purchase an inflation needle. Generally, most footballs, soccer balls and basketballs require a universal-sized needle. However, if you are unsure about the valve size on your ball, take it along when purchasing your needle to ensure you buy the correct size.
Locate the valve on your ball. The valve is the small hole that provides access to the inner rubber bladder. It is usually surrounded by a thin rubber circle. On a basketball or soccer ball, the valve is commonly located immediately above or below the size and weight information. On a football, the valve can be located centrally, above or below the laces.
Lubricate the valve with some water or saliva.
Insert the lubricated needle slowly and at a right angle to the ball. When you hear the hissing sound of air being released from the ball, hold the needle in that position. Hold the ball tightly to squeeze out the air and prevent the needle from snapping.
Once the ball has reached the desired level of deflation, slowly remove the needle and store it safely.