A little offhand perspective from a Highpower Across the Course simpleton.
As others have said and mentioned above, there's some good books/manuals on there. "Ways of the Rifle-2009"is definitely a good one, even if seemingly geared more toward the air rifle/smallbore shooter.
Natural Point of Aim. It's enormously important, yet I see lots of folks who go up to the line, generally get their position and that's it. No or not enough small refinement shifting. If my NPA is off, either initial set-up or body settling in during a string, I find that my wobble size will increase. That's from slight muscling of the rifle. A quick NPA check will confirm that and I'll adjust.
Don't lie to yourself either. Settle into position, close your eyes, breathe in, exhale, open your eyes and accept what you're pointing at. DO NOT MUSCLE THE RIFLE TOWARD THE BULL. Then shift your position.
I firmly believe that too many folks are not truly getting their NPA correct and that becomes a major problem.
Recognizing misaligned NPA can also help with other shooting disciplines and field firing as well.
Your body is balanced by the inner ears. With that said, have the rifle pretty high up in your shoulder and cant the rifle inboard. The cant allows you have an upright head position.
This will probably require a windage (possibly elevation) correction. I normally have 1 1/4 MOA of right wind on my rifles (both Match and Service) to compensate for my cant.
Look at where the buttstock is going in your shoulder, don't rely on feel. This will ensure proper placement of the buttstock each time. In my case, I'm looking at specific creases or locations on my shooting jacket. Mark the best spot on your clothing with a pen, have the buttstock hit that spot each time.
Ensure your cheek is pushing down into the buttstock in the same spot/same pressure. I like to have my chin touch the buttstock or cheekpiece at almost 90 degrees offset to the bore and turn my head while pressing my cheek down. Get's the chipmunk cheek thing going and helps ensure my head position along with consistent head pressure on the stock. I prefer the "nose-to-charging-handle" spot on Service rifles. Worked when shooting irons and I have Service Rifle scopes set up to work the same way.
Keep the rifle fairly close to your body. Too far out (guess you could say "open") will mess with your center of gravity. My son had this problem when he started shooting.
Figure out your wobble area. This ties in with NPA. Set up aimed at a blank wall. Build your position, and get a feel for it. When are you most steady/stable? Then add a target and adjust your NPA that way.
Watch your trigger control. It's easy to get sloppy and try to snatch the trigger too fast, leading to jerking. Two stage triggers can help with that.
Another one that many folks have a hard time with is knowing when NOT to shoot. Many will hold on and try to dress up a shot while their position is failing, blood oxygen is dropping, and the image is getting burned into their eye. I try to have the shot gone within 7 seconds of exhaling and focusing on the reticle (or front sight if irons). If not, I breathe and start over. I might not take the rifle out of my shoulder, just breathe, shut my eyes and/or look away, then start the shot process over from that point. If stability is falling apart (NPA shift, usually), then I'll take it out of the shoulder.
Air rifles and .22's are great trainers. They allow you to work on the mechanics of the position and shot execution while forcing you to improve followthrough. As another poster stated, that longer projectile dwell time in the barrel is the key. Easier for you to throw off a shot with an airgun/.22. I've got an Eliseo AN-1 set up as a Match rifle trainer and a Compass Lake dedicated .22 LR upper as a Service rifle trainer.
I have a SCATT electronic trainer that spends probably 99.57% of its time set up to practice offhand. There's a lot of data that you can glean from the SCATT.
If you really want to get good at position shooting, like others have said: PRACTICE.
Big wall of text.
it was fun but definitely a bit of an eye opener. So not trying to be super great or anything when it comes to off hand or positional( not going to lie kinda wanna build a cheap little m16 a 2 flat top now just for this 
) just not as terrible. Any tips y'all got ? Figure there's a few Positional guys on here.
