If you apply makeup with your fingers, use your ring finger. This is your weakest finger, so it applies less pressure and is gentler on the delicate skin on your face.
Dark circles
You're tired. You know it, but nobody else needs to! Cover your dark circles with yellow concealer, just a shade lighter than your natural skin tone. Set the concealer with a powder to help it hold. Choose a powder with a bit of shimmer to reflect the light, and line just the tops of your eyes with liner to draw attention to the tops of your eyes and not the bottom.
Puffy eyes
Puffy eyes happen for a lot of reasons. They are triggered from cold and allergies, tiredness and even crying bouts. Don't hide your puffy eyes – send them packing! Apply anything cold to your eyes for 5-10 minutes. Cold tea bags work great, so stick a few used ones in the fridge instead of throwing them away. You can also use a cold washcloth, chilled cucumber slices or spoons you've chilled in the freezer. If you don't have 10 minutes to wait, use a hemorrhoid cream to help the puffiness fade.
Blemishes
We all get zits, but that doesn't make them any less embarrassing. When you wake up with a pimple, hold an ice cube to it for five minutes to reduce the swelling and redness. It'll look better after that, but probably will still need a cover up. Instead of using concealer, which lightens the blemish and actually tends to draw attention, try a liquid foundation. Choose a shade that matches your natural skin tone and dab it on your problem area. Blend carefully with your ring finger, and no one will know it's there!
Scars
Even the largest of scars can be dealt with using makeup. Start with a concealer, and choose the color based on your scar. If your scar has a red tone to it, choose a green or yellow concealer, and a mauve concealer for a scar with a blue shade to it. If your scar is on the smaller size, use a sponge or your finger for application, but stick with a sponge for larger scars. Follow the concealer up with an all-over foundation to even out your skin tone, then use a powder to set the look.