 Better use a makeup brush, beauty sponge, or your fingers to apply makeup. Brushes need to be cleaned often and require more blending time. When you use a dirty brush, you're at risk of getting fungal infections, E. coli, or even a staph infection. Sponges act like, well, a sponge and soak up a ton of your product, not to mention their perfect breeding ground for bacteria. Using clean fingers actually has the most product payoff and your hands are cleaned way more than your brushes are. Don't lie. The warmth of your fingers helps blend the products into the skin and you'll actually end up saving on products since it won't get absorbed.