Your neck holds your head up, houses some very important veins and arteries, bones and is the area where your spinal cord is most exposed. Neck exercises will not only lessen the possibility of injury and concussions, but will also make you look bigger than what you might be.
A neck exercise you can do at home or at the gym:
Position yourself face down on a flat bench with your head hanging over the end. Place a folded towel or t-shirt on the back of your head and rest a 5kg weight plate on it. Using your hands, steady the plate and simply nod your head up and down. Repeat this about 15-25 times for one set. Increase the number of sets as you get stronger.