If you are neglecting your neck, you are neglecting your health.
I start and end all training sessions (both with clients and my own sessions) with neck work.
The more you can move your head [flex, extend, rotate, laterally bend and combinations of], the more of your world you can see.
Investing in your neck mobility will support the function of your nerves. You have 8 nerves that exit your cervical spine. These nerves control your reflexes, muscle actions and sensations. The more you take care of your nerves, the more you can interact and perceive your world.
Here are some of my favorite neck mobility movements and static stretches. Incorporate the neck mobility movements before and after your training session. Add the static stretches in at the end of session.