Reduce Shoulder Tension
Tight shoulders often translate into a tight neck. One particular culprit in this equation is the trapezius muscle (learn more about the trapezius here). This muscle covers a triangle-shaped area in the upper back starting at the bottom of the shoulder blade, running out to the shoulder joint, then narrowing to climb the side of your neck. When the upper part of the trapezius is tight, your spine can feel compressed. A quick, desk-friendly remedy to release built-up tension is shrugging your shoulders in an exaggerated fashion: inhale and raise your shoulders to your ears and exhale letting them fall — really give into gravity and let your shoulders drop. Repeat this action four to five times. Follow it up with a self-massage: use your opposite hand to squeeze this muscle just like you would a wet sponge. Imagine you're wringing out the tension with each squeeze.
Create Some Motion
Stiff necks crave a little motion. I'm not suggesting headbanging to your fave Iron Maiden jam, but doing subtle neck stretches will certainly help. Swaying your head slowly from side to side can help ease tension through your neck. Make a half circle with your skull by bringing your right ear to your right shoulder, then roll the head forward bringing your chin to your chest, continue to the left bringing the left ear to your left shoulder. Reverse directions, dropping your chin and rolling your head to the right. Repeat a few times in each directions. I suggest doing this stretch throughout the day to prevent stiffness before it starts.
Learn one more way to relax your neck when you keep reading.
I hold a lot of tension in my upper neck. To get movement at the top of the spine — where the skull meets the neck — try drawing really small circles with your nose. It helps to have a relaxed jaw for this move, so if you're a clencher, here's a jaw release to do first. For the circles, just trace small circles in the air with your nose. I know it sounds a little silly, but these circles should be so small the people sitting next to you can't see the movement. Draw 10 in one direction, then reverse.