If you get a streak or blotch of paint in your hair, the first thing to try is to gently scrub it out using the tips of your fingers and nails. This method is quick, easy and effective, especially if the paint is water-based. If it is oil-based, you will need to use a bit more force, but it will still work well.
If the paint is still a bit stubborn, shampooing with a grease-cutting product can help. If you have a bottle of hand soap that contains glycerin, this is an excellent choice because it works to break down oily substances and can often dislodge paint. If you have a mild dish soap that is gentle and can remove stains, this can also be effective.
Another option to try is baby oil. This can sometimes be helpful in removing oil-based paint from your hair, and it is one of the least expensive options on this list. Apply a bit of the oil to a cotton ball and rub the painted areas of your hair. You may have to repeat this a few times before the paint starts to loosen up.
If you are unable to remove the paint with any of these methods, it is time to bring out the big guns and use a solvent such as turpentine or mineral spirits. Be sure to use these in a well-ventilated area and follow the safety instructions on the label. If you are able to remove the majority of the paint, wash your hair with a gentle shampoo that is designed for dry or colored hair and then use a wide-toothed comb to pick out any remaining bits of paint.