I've been annealing for decades, find it more of an art than a science. I've tried most everthing available except the temp sensitive paints and markers. Started out doing it really bad and have progressed to where I'm quite happy with the results.
My early efforts followed the "heat necks until they are a bright red and tip them over in a pan of water" method. Bad way, at least for me; red hot is FAR TOO HOT and I couldn't do it evenly. Too much heat damages the brass alloy and leaves the necks dead soft, with very little real bullet tension/grip.
Finally got a little smarter; Tried hand holding the cases at the head in my fingers while heating the necks. Aimed the inner blue tip at the junciton of neck to shoulder while turning the cases for an even heat treatment. Safety comes in that when they get too hot to hold they are immediately dropped into a water bucket. That was a better method but some torches aren't quite hot enough to get the necks up to the right temp before my fingers smoked!
Finally, I lathe turned an aluminum case holder device that looks a lot like Hornady's annealing holder. Mine has a small, 1/4" diameter, holding stem about 3" long on one end that's easy to hold and spin in my fingers. The working end, the fat end, is about 3/4" by 2" and bored 1/2" by 1 1/2" deep. I can drop most any case heads (escept magnums) into. I can easily hand hold/spin it at a slant with a case in the torch flame for even heating and then drop it into a water bucket when I see the shoulder-body junction turn the "right" shade of light blue - it's a learned thing. That method works well and it's the only way I would suggest today.
You could easily duplicate my case holder with a 9/16" or 1/2" deep wall socket (ratchet wrench) and a short socket extender.
I like standard propane torch fuel, MAPP gas gets much to hot to fast for me to accurately judge shoulder colors.
