This stretch is one you can do sitting down, which is great when you are tired from a long day! I always have tension in my neck muscles, so I really love this stretch and try to do it often.
Place one hand on the opposite side of your head over your ear, and gently pull your head towards your shoulder. Sit up straight and keep your shoulders down to get the deepest stretch - it can help to sit on your other hand to intensify the stretch! You should feel the stretch in the side of your neck, and you can hold this as long as you want. I also like to slowly roll my head around to stretch the front and back of the neck as well.