About 40 years.
Seriously, I never sought instruction and thought I could just learn on my own. Well, there are things you need to know about technique and the biggest is CONSISTENT draw! Took me a while to figure that out.
I got my first little kid's laminated fiberglass 25 lb bow when I was about 12. I tried and tried and couldn't figure out how to quit losing arrows in the grass. In college in the summer of 1973, I was working in south Texas counting cotton insects for a research project through Texas A&M's ag extension service. One of the guy's had an old Colt plainsman 45# recurve and I traded him 4 eight track tapes for it. Over the years, off and on, I'd try and fail and give up. Biggest problem was I was not drawing to a consistent point with the bow string. Also, instinctive shooting is tough, takes LOTS of practice to learn how to guesstimate range elevation as the arrow is not at eye level. Getting the windage is just a matter of sighting down the arrow, but learning to elevated is a pain. Lots of shots over and under the target. Arrows disappear in carpet grass.
So, about 6 years back I had been reading online about proper technique, kisser buttons, all that. Then I had an idea, to put a nock at eye level and put marks on the bow to better "aim" for elevation. It worked pretty well, but was hard for me to line up quickly which must be done with a stick bow as it's not easy to keep at full draw. Meanwhile, I ebayed a 90s Hoyt Hunter compound and rigged it and found out I could actually, with the sights properly adjusted and after a month or two of practice, keep all shots on a paper plate at 25 yards. I've since gotten pretty good even with my weak eye out to about 45 yards with the compound. But, I still had problems with the stick bow judging elevation.
My old Colt Plainsman busted, bought a PSE Kingfisher (mostly for bow fishing) and recently a friend gave me a Bear Stag Hunter 50 lb recurve in excellent condition. I bought a string for it and started playing with it, again. My consistent draw gained from practice with the compound seemed to help a lot, but I still had problems judging elevation. Then, I was watching the movie "Mongol, The Rise of Genghis Khan" the other night, excellent movie if a little slow, and in the battle scenes I noticed they had a red string tied from bow to string. I'd thought this might be an elevation sight, but turns out they did that to limit draw length in the interest of a consistent draw while shooting from odd positions on horse back (googled that). But, ever the tinkerer, I got some sight stretch tubing I had in my archery box and tied it from the bow to the bowstring at eye level, played with it adjusting it up and down the bow until I could, from 25 yards, consistently hit proper elevation. It works FANTASTIC! I couldn't quite believe how well it worked at first. I know it's not "instinctive", okay, I'm a lazy wuss who tries things, ain't that how the compound got invented in the first place? I look down the arrow for windage and can see the elevation string/rubber in the same focus, sorta like looking down a tube or something. I pull, see the elevation and the arrow and line up windage and elevation at the same time and release much faster than trying to use sights and pretty danged accurately! I can still shoot better with sights on my compound and have sights on my Kingfisher recurve. Maybe it's because of my weak eye, but shooting the recurve this way is a LOT quicker than trying to pick up a sight pin through an aperture or lining a nock with a mark on the bow as I'd tried already. I'd be real proud of myself for this, but it took me until I turned 60 to figure it out!
If you plan on learning to shoot instinctive, not using any other system, no matter how simple, to judge elevation. I think you're going to have to first learn techniques, developing a natural, consistent draw, then lots and lots of shooting to master the judgment of elevation. I look at guys like Byron Furguson and just marvel at their skill set. I don't think I could get that good if I were trained from birth like a Mongol. But, I'm pretty efficient with my elevation string to 30 yards with the recurve, now. After I finally take a deer with my compound, I might try it with the recurve. Don't have a long bow, but little is different from a recurve, really, far as technique goes.
Just my $.02. I'm sure not God's gift to archery as you can probably tell. Took me this long to want to go bow hunting.
I've done rifles, black powder, and pistols. I need to go after one with a bow. I think I'll not go so far as wasting a 5 dollar arrow on a squirrel, though. That's why God gave us .22 pistols.
