Tip #5: While we like to blend concealer using our fingers, the best makeup brush to buy is flat with densely packed bristles. A dome-shaped tool like the Sigma Beauty F65 Large Concealer Brush ($21) will help you get into the smallest crevices.
Tip #6: If you want to erase tired, sagging eyes, there's an important product you have to apply even before concealer — corrector. While your concealer product will even out your dark circles to match your skin tone, a color corrector brightens the entire area by neutralizing the blue or green undertones. "Correctors come in peach or bisque tones," said Bobbi Brown makeup artist Kim Soane. "The peach color eliminates gray and green, and bisque (or pink) takes away a gray/blue/purple undereye."
Tip #7: You've probably been dotting concealer on in a half-moon shape for years, but an inverted triangle is the better strategy. Not only does it help draw attention upward toward the eye, but it also helps sculpt out the cheekbones. Make sure to extend concealer all the way to the inner corner of the eye.