Awareness, in and of itself, is the backdrop for positive change. By bringing a bit of awareness to that head bob, you’ll find your nerves (and often accompanying body aches) releasing into ease.
Give it a try:
Sit or lie quietly.
Begin to nod your head as slowly and simply as you can.
Let your nod be VERY small and VERY slow. Stay in a range where the movement is easy and effortless.
Continue to nod in this way until your breathing becomes easy and regular.
Let it go and notice the changes.
For even more benefit, use your powers of observation and take notice:
How do your eyes move when you nod your head?
What happens along your spine as you nod?
If you are sitting, does how you take weight through your feet change as you nod your head?