One of the easiest ways to make a younger actor look older is to grey his or her hair. While there are hair color sprays made just for this purpose, these products have drawbacks: the aerosol propellant is bad for the environment, the cans get used up too quickly, and the results often look fake (too blue or too silver, and too obviously applied only to the top layer of the hair). Clown white greasepaint, in my opinion, has a natural look, and is much cheaper.

Use an old toothbrush to apply the makeup. Lightly dab the bristles into your container of clown white and brush it into the hair, starting at the hairline (use a light hand for this - it's easier to add more if you don't have enough than it is to fix an overload). For light graying, brush it back just from the temples; for an all-over effect, start at the temples, move on to the hairline at the forehead, and continue on to the back of the head. Don't try to coat every hair, and brush it through thoroughly to let some of the actor's own hair color come through. If you get too much on in one spot or if it looks blotchy, wipe your toothbrush on a paper towel and brush it through the heavier spots to get the clown white more evenly distributed, or use a regular hairbrush on it (although you'll have to wash it later). Although you'd think clean-up would be ghastly, it all washes out with shampoo.

Clown white greasepaint can also be used in conjunction with gray spray to add a more natural streaking effect to the hair. A single container of clown white and your trusty toothbrush will last you through many, many shows.