The next time you're traveling, in a hurry, or out of concealer, here's an easy way to MacGyver your way into hiding your blemishes. Grab a cotton swab or makeup brush, then dip it into the cap of your liquid foundation. The accumulated foundation here is usually thicker, so it can double as concealer in a pinch. Better still, the "concealer" will match your foundation perfectly. Obviously, this trick won't work every day, because the foundation needs time to thicken, but it's worth a shot when you're in a pinch.