Blot - don’t rub. Rubbing can spread the paint deeper into the fabric. Place a clean cloth or paper towel behind the stain and gently scrape away paint with a dull edge. Wash the garment according to its care label once the paint has been removed.
Protect any unwanted areas with an apron, gloves and/or drop cloth. If spray paint gets on the hands it can be removed with heavy soap and water and scrubbing.