Want strong sexy looking shoulders, try doing upright rows. The upright row strengthens and develops the top portion of your shoulders and trapezius (the muscle at the top of your shoulders that attaches to your neck). Perform this exercise at the cable machine. Attach a straight bar and place the pulley at the lowest level. Grip the bar at a position where your hands are about an inch apart and stand upright with your arms full extended. Position your feet shoulder width, slightly bend your knees, and lift your chest high. This is your start position. Pull your hands to the top of your chest all the while keeping your elbows slightly higher than your hands and then return to the start position. Exhale as you pull the weight upward and inhale as you return to the start position.
I recommend beginners do 2 sets of 10 repetitions of this exercise and those more advanced can do 3 sets of 10 repetitions.