The best makeup for a 12 year old is a light, natural look. This means using light colors, such as pinks and nudes, and avoiding dark colors. Avoid heavy foundation and concealer, and instead opt for sheer coverage with a tinted moisturizer or BB cream. When it comes to eye makeup, opt for neutral colors such as browns, taupes, and golds, and avoid dark colors such as black and navy. Finish off the look with a soft blush and a light lip gloss.