Strengthen your back to align shoulders for a "natural boob lift," says trainer Harley Pasternak, who works with Megan Fox. His go-to exercise? While holding 5 lb. dumbbells, bend at the waist so your torso is parallel to the floor. Bend your arms at the elbows and pull the weights up in a rowing motion. Lower, and repeat for two sets of 12 reps. A less strenuous way to heighten allure? Dab shimmer on your décolletage before hooking your push-up bra.