The Makeup Wakeup, a new book by beauty editor Lois Joy Johnson and makeup artist Sandy Linter, is full of sharp advice. For example, did you know that when you're buying foundation, it's a good idea to test it twice: on your jaw, and on the back of your hand as you make a fist? The first test helps you find the right shade; the second—once you relax your hand and the skin loosens—lets you see how the makeup texture will look on expression lines and dry areas.