Hi all!
This is one of those areas in which everyone is a bit different, and it takes a bit of experimentation to see what works for you.
A basic rule of thumb is that it should be "strong side", with a muzzle rear cant. This will allow a nice smooth draw that is perfectly in line w/ your intended target. It is also very safe because you never end up pointing the firearm at yourself during the draw sequence.
Because each person's anatomy is different, the actual location (and subsequently the rake angle) is not something that someone can tell you. I would suggest that you wear your firearm around the house shoved in your waistband (w/an empty chamber) in different locations from 3:30 to 5:30 and see what feels right to you. Once you've done that and pretty much determined your preferred location, you'll know what to tell your holstermaker as you search for a holster design that you like.
My Max-Con V and VI are raked at approx 25 degrees because they are intended to be worn at about 4:30 to 5:30 and the increased rake angle makes drawing from that location a breeze. Conversly, the Max-Con III is raked at about 17 degrees as it is intended to be worn from 3:30 to 4:30.
Please feel free to contact me w/ any questions that you may have. (You don't have to order something in order to get a free consultation over the phone

This is a tough thing to decide until you have some experience. Perhaps I can help you get started in the right direction without your having to spend a fortune on holsters during a "trial and error" process. Good luck!