The key to developing arms that look great from every angle is toning the muscles that make up the largest part of your arm: the triceps. To develop them correctly, "you need to tone all three muscles that make up your triceps muscle," says Jeff Bell, a celebrity trainer and owner of Bell Fitness Center in New York City. The following multiangled moves offer a thorough workout that completely shapes all three. Try this routine two to three times a week, resting at least 48 hours in between.

You'll need:
A mat or carpet, a step platform, and a set of light (two to three pounds) and medium (five to eight pounds) dumbbells. Work up to doing 10 to 12 repetitions of each exercise before moving on to the next.

One-Arm Cross-Shoulder Extensions
Lie flat on the mat with knees bent and a light dumbbell in your right hand. (A) Raise the weight over your head, arm pointing straight up, with the dumbbell facing left. Place your left hand on your right triceps to help support your right arm. (B) Now slowly lower the weight to the left until it lightly touches your left shoulder, keeping your wrist straight and your right upper arm still. Raise the weight back overhead, then repeat. Do one set, then switch sides.

Lying Dumbbell Presses
Hold a light dumbbell in each hand, and lie on your back, knees bent. Extend your arms straight above your shoulders toward the ceiling, with palms facing forward. Keeping upper arms stationary, slowly bend your elbows, and lower the weights to the sides of your head. Simultaneously rotate your wrists in so your palms face your ears at the bottom of the move Press the weights back to start, twisting your palms again, and repeat.

Close-Grip Dumbbell Presses
Lie on your back with knees bent, and hold a medium-weight dumbbell in each hand. Raise the weights above your chest so your arms are fully extended toward the ceiling, elbows unlocked, palms facing forward. Touch the inside ends of the weights. (The closer they are, the more of your triceps you'll work.) Slowly lower the weights, keeping them together, until they reach your chest, then press them back over your chest.

Triceps Dip
Sit with your back to a step platform, and wrap your hands around its front edge. Spread your fingers so that little fingers are pointing to the platform's outside edge (doing so will help keep your elbows pointing straight back instead of bending to the side). Extend the legs, heels on floor. Lean back at a slight angle so that weight is shifted to the back of the arms (this helps target the triceps), then lower and raise your body. Perform two sets of 12 to 15 reps.