I've cut my own for over 30 years now. Got my hair gene from mama's side, which
meant thick and curly. I spent many years getting it cut by all manner of establishment,
but my hair didn't fit within everyone's set training and they botched it more often than not.
Figured what the hell, I can eff it up as good as they can - free of charge!
Once I studied what they were doing, then fetched my own hair clipper set with attachments.
I used to snap on the 3/4" hair length thingy, but I've used the 1/2" attachment the last decade
or so as I keep it shorter now.
Simple, really - clippers with attachment, "comb" it in the direction you normally comb it anyways
(work it with the cowlicks and waves and such, not against them), repeat until it's not cutting anymore.
A decent clipper set pays for itself pretty quick, since I still have to cut my hair every few weeks.
Oh - and these days, holler at the wife when done so she can fix up the back.