Ok. So the reason, you got so much hate in the first few pages of this thread is because the more experienced riders know what it looks like when someone doesn't really quite know what they are doing, but is just hucking the ever-loving crap out of themselves on jumps. This is one of the most cringe-inducing things you can see in the park because it is usually some young kid that has no business trying to do the tricks he is attempting and he looks like a complete moron doing them. The funny thing is this kid usually is the joke of the entire mountain because he thinks he's all bad for almost landing backflips and 3's, but since everything is ugly looking everyone just laughs about him behind his back. Now I'm not saying this is you, but all of those bad reactions you got on the first page was probably because it really made people seriously believe you were one of those kids.
The funny thing is that I know exactly how you feel, though, because my close friend and I were those exact kids in the park several years ago. Let me be the first to tell you that you're doing it wrong. I didn't realize it until I broke my left arm and my best friend got a concussion the same day on the same jump. We kinda sorta had 180's down, but we had no clue what we were doing. We were hucking the crap out of some 3's but didn't really know what we were doing. It just made sense to use because we had tons of skating experience. Eventually if you ride out of control, something will go wrong and you will wreck yourself pretty quickly. That same friend of mine didn't really know how to do 3's flawlessly, but was throwing down backflips like it was his job because he thought it made him look cool and made him look like he was a really good rider. He eventually tore his shoulder and it put a very quick end to his progress as a snowboarder. Think about it this way, if you're out of control and break an arm/tear something, you will immediately stop your learning progress for that season and will have to start all-over next season. What we eventually learned, instead, is that it is WAAAY better and faster to learn tricks if you just take it slower and build up to more difficult tricks one step at a time. Instead of taking 2 seasons to learn 3's, because you wrecked yourself, you can do it in 1 season because you were smart about it.
So, now that we got that out of the way, here are the real tips to learn to do 3's. You need to have very good solid edge control and you have to understand how to approach the jump with a good "set-up carve". Depending on if you are spinning back-side, front-side, or front-side off your toes, the approach will be different for all three ways to spin. Luckily, you can learn to master this approach by just doing 180's. If you keep working on this same "Set-up carve" approach over and over until you can bust 180's with basically any and every grab you can think of, then 3's will literally just fall in to your lap. But I REPEAT, do NOT work on 3's until you've master the approach and set-up carve by mastering 180's. Plus, the more solid you can land 180's, the easier your 5's will eventually become. There are a ton of good videos on how to do this set-up carve, but I would check out snowboard addiction because the way they present stuff is flawless. Do everything in their videos and do NOT progress to 3's until you've mastered straight airs and 180's. I know this sounds "beneath you" because I thought it was beneath me too when I first started, but I swear to you this is the fastest and best way for you to learn how to kill it in the park. In all reality, no real snowboarder will give you props for throwing down sloppy back flips and sloppy 3's if you have no clue what you're doing, but you will get WAAY more respect for dropping steezy 180's than sloppy 3's. Then once your 1's are on point, you will start to throw smooth steezy 3's and you'll be golden.
And for christsakes, stop doing backflips for a few seasons until you at least get 3's and 5's down. You're not impressing anyone.