Start by looking straight ahead. Slowly lean your head to the left. Using your left hand for resistance, use the muscles in your neck to press against it. Hold for five seconds, then return to starting position. Then, slowly lean your head to the other side. Hold for five seconds. Return to starting position. Do ten repetitions. This is a good exercise to do during work, especially if you have to keep your head in a steady position for extended periods, as in working at a computer. Do this exercise every half hour to prevent neck strain.