I have cut my own for years. I started by cutting DH's, with a Phillips hair clipper that went up to a 42mm setting. Then I got fed up with getting cuts from professionals that were nowhere near what I had asked for, so I tried on my own hair - and since then have never paid a hair dresser for at least 30 years. The original clipper wore out (in mid-cut!) so I had to buy another, but Phillips still make one (the 9000 series) that goes up to 42mm - as far as I can tell it is the only one on the market.
In fact, I suspect it cuts my hair longer than that - maybe 50mm, which is about two inches. I avoid cutting the front where it frames my face, and trim this a bit longer with scissors. There are interchangeable combs which guide the hair into the cutters, and feed it in at the appropriate length, so there is no chance of getting a "baldy" by mistake! This made it possible for me to allow DH to cut the back, where I couldn't see whether I had caught all of it. I wouldn't have trusted him with scissors! Nowadays I have to do that myself (or ask a passing daughter or female friend) but I have evolved an effective technique - which I will detail later if anyone would like to know it. The instruction leaflet rather glosses over that part.