The process is pretty simple, but the kit is essential. I have done it a few times on a couple of different Avid systems. You need the kit because there are a couple of required connectors to hook into the fluid ports at either end of the system along with syringes for working the air out. First one took the longest. Did my wife's bike last year in under an hour.
hayes and avid are pretty easy but i use the kits - two different ones required the after market kits have worked fine for both, just read the reviews and check the contents to make sure they have everything for your specific brake.
i'm by no means an expert wrench - just cheap and don't like giving up the bike too long. i just follow and the youtubes!
Bleeding is easy with the right tools/kit, but pay attention to your fluids ,some recommend mineral oil,actually best for most but has low boiling point. Standard DOT fluids are glycol based and absorb water, you want to use DOT 5 which does not