I've read magazines, books, articles online... Other people learn in different ways, but I always learn these types of skills best when I have a mentor. I've been hunting, mostly unsuccessfully, since my late teens. If you can find a mentor to show you how to do it (the hunting part, that is), the rest is easy. Here are a few pointers that may help:
1. The first deer I field dressed, I did it by following an instruction card. Yes, laid that fold-out, waterproof instruction guide out on the hillside, and started cutting. If you've ever gutted a rabbit, or other small mammal, the same principles apply. You can find plenty of youtube videos illustrating this, so watch a bunch of those, and you'll be ready.
2. Save yourself a lot of pain: don't try to drag a deer more than a couple hundred yards. I once met a man who was 73 years old, dragging a deer he had shot that morning. He had shot it at 9:00. I met him at 4:00 PM. He still had a mile to go. I offered to help him, so off we went. That buck just about killed both of us, even though it was wrapped in a tarp, the ground was level, and the trail well-established. I ran into him later that week, and he said that when he got it to the butcher, it weighed 195 lbs (field dressed and dragged all day in the sun). Dragging deer is no fun. Get yourself a cart for those medium-length hauls (1 mile or less). For hauls longer than a mile, get a large, framed backpack. Learn to debone the carcase, pack it in bags, stuff it in the pack, and walk out. You'll be glad you did.
3. Butchering: years ago, a buddy lent me a VHS series about butchering your own deer. Some of the stuff I had already figured out, but there were some good pointers on it. I'm sure you can find some good stuff on Youtube on how to do it yourself. I find that if I get a lightweight food storage bag (not ziploc), or produce bags, wrap each cut in that and squeeze the air out as I roll the meat up in it, then wrap in butcher paper, it will last about a year (sometimes more) in the freezer. You can get it professionally done, but it will cost you $100-$150. Also, de-boning in the field negates the need for butchering, unless you don't have a meat grinder.
4. Gutless deboning: my hunting partner was skeptical, but this method I read about a while back really works, and can save you some time and effort, especially if you're packing it out. Here's a video of it: http://www.youtube.com/watch?v=WZsO4tsrKPw and http://www.youtube.com/watch?v=NXuOq4jz34A&list=PL91058FB839915299
The first video didn't show how to remove the front shoulder, but if you begin underneath it and work your way up to the joint, and cut through the tendons and ligaments, it comes right off. If you're into eating the heart and liver, you'll obviously have to go in and get those afterward.
5. Havalon knives are cool!
6. Get good optics- binoculars, scopes, rangefinders, spotting scopes, etc. The general rule of thumb is "buy the most expensive ones you can afford". For me, that means a lot of Leupold glass. For others, that means Swarovski.
7. Bow 'n Arrow shop in Lakeside, if you're an archer, or want to be. And you should want to be.
8. When you find a spot that has deer, but no people, make sure you PM me. ONLY me. Otherwise, you won't be alone next time you hunt there. Remember, only tell El Matavenados. ;-)
9. Quail and coyotes are no fun to hunt, so make sure you give me the gps coordinates of every single one you see. I'll take care of them for you.
10. CA deer are internet savvy. They know PRECISELY when the season opens and closes. They will stand there and look at you from 30 yards 1 week before the season, but you won't get near them when it's open. They also know that you're not allowed to shoot them with a rifle in the recreation area on Laguna. So you'll see plenty of them staring at you from 60 yards away when you have a bow in your hands. Put a rangefinder up to your face, though, and they're gone.
11. While you're buying maps, you might as well get the BLM Maps for SD County. CNF isn't the only place to hunt around here.
Go get 'em!