Paintball paint is water soluble so it will come out of fabrics and clothing pretty easily. If you are trying to get it off of the side of a house or a car, though, it is a little trickier. But it still only involves a couple of cleaning products. When participating in paintball, do your best to not hit objects you will have to clean later.
1. Put all clothes and fabrics into the washing machine with laundry detergent as you would usually clean. It is best if you wash them as soon as possible, as the longer the paint sets in the fabric the harder it may be to get out. Wash the clothes as usual and dry.
2. Get a scrub brush and cleaning solution if the paintball residue is on the side of your house or aluminum siding. The best concentrated solution that seems to work is called Simple Green concentrate. Pour a capful of this into a bucket, fill it almost full with some warm water and swish it around to make it sudsy.
3. Douse the area in water that has paintball residue on it, either with a sponge or a hose, to get rid of any surrounding debris or dirt.
4. Dip the scrub brush into this mixture and scrub firmly at the paintball residue in circular motions. Repeat this procedure until the paint is gone, then rinse it off with clear water from a sponge or hose.
5. Clean paintball residue from a car in the same manner, but skip the scrub brush so you do not scratch or dull the car paint. Use a rag and dip it into the cleaning mixture of Simple Green and warm sudsy water. Rub in vigorous circles at the paintball residue on the car until it is gone. This may take more time because you are just using a rag, but it is better than damaging with a scrub brush.
6. Rinse the car area where the reside was with clear water from a hose or sponge.