1. Buy a set of clippers with guides.
2. Line up your guides by size.
3. Put the highest number guide on the clippers and go for it. I start in the front for a few reasons. First of all, you usually want the hair to be shorter around the ears and back (a smaller guide), this way the clippers do most of the blending for you. Second, the kids get more wiggly as you go, so you can hide the mistakes in the back.
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5. Change to the third guide and do the nape of the neck and around the ears.
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7. If you are really lucky, this will be the result:
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Bug was great and didn't move at all. Little Man doesn't sit still at all, so this really was pure luck. Little Man always ends up with "spots" where he's moved his head when I wasn't expecting it.
As for the guides... with Bug I used a 6,5 and 4, Little Man is a 4,3 and 2, and Wil is a 4,3,2,1 and flat clippers on his neck. You have to find what works for you. Some people tend to go longer in winter, shorter in summer. I know how to do it one way and that works for me. In the winter we just wait a little longer in between cuts.
Hope this helps! Remember, this is something I've picked up from watching the barber and stylists... the clippers really are the key. Plus, it's just hair and grows back quickly.