You're in for one of the best feeling you've ever had!

That being said, get it clipped as close as possible, the so called zero guard. Next--take a nice warm shower and really soak your head, even use some shampoo and conditioner. Leave the conditioner on. Then, apply the shaving creme--you'll find whether a gel or Headslick (my favorite) works best later. Take a FRESH blade, and TAKING YOUR TIME shave your head. Usually, going from front to back on the top, then from bottom to top on the sides and back. Rinse, reapply some more shaving creme, and carefully and slowly do it again. Rinse well with warm water, then cold, or an ice cube is even better. Look in the mirror--you're Sly Dude--

Now, some astringent, hydrogen peroxide or witch hazel, whatever you have, applied w/ a cotton pad is easiest IMO. Now, when dry apply an after shave balm, I find Nivea Extreme great, but whatever.
You will find that you'll have a couple of red spots, etc., don't worry they will go away.
That's it. You may feel a numbness on your scalp, it's wonderful, but it too goes away--but you'll always remember it.
FINALLY--sunscreen--minimum 30spf. You're good to go. ENJOY