Pre-soak your white uniform before machine washing it. Use a wash tub or a utility sink to accomplish this. Fill the tub with warm--not hot--water and then add a cap of laundry detergent and baking soda. Mix that solution thoroughly and place your uniform in it for about one hour.
Use an oxygenated bleach to clean out stains. Do not use a chlorine bleach--it is not effective on a polyester uniform. Oxygenated bleach will get stubborn stains out.
Machine-wash your uniform in cold water. While most white clothes can be washed in hot water, this is not true for a white football uniform. Use cold water and a mild detergent.
Wash your uniform alone or with other white football uniforms. Do not wash them with ordinary clothes. Most cotton clothes give off lint, and the lint will attach itself to your uniform, giving it a careworn look.The lint will attach to the numbers and letters on your uniform.
Dry your clothes on a line. A football uniform that is placed in a dryer will shrink. Additionally, if there are any stains, they will get set in the uniform by the drying process, and the colors will fade.