Eh, here we go... I can do all the three major smoke tricks, so I'll try and relate the info;
Kill Hit - When one allows smoke to float out of their mouth while simultaniously pushing out with your tounge, idealy forming sort of a 'ball' of smoke, then quickly breathing it back in through your mouth.
How to do it - Probably the simplest one of all... open your mouth, let some smoke go out on its own or push it with your tounge, then breathe back in through your mouth. Nice and easy. Really fun when smoking weed, drives the smoke in nice and deep.
French Inhale - When one lets smoke float out of their mouth or pushes it with their tounge and simultaniously breathes it in through their nose.
How to do it - Again, pretty self explanatory... to do it right though, it's almost nesscessary to use your tounge. Open your mouth for however much smoke you can handle in your nose. I've heard some people argue that doing this constantly, particularly with a joint, will get you higher. Same type of thing with snorting a pill vs. swallowing it. I personally don't know or care if it's true... it's fun to do and looks cool as all hell.
Smoke Rings - The act of blowing a smoke ring out of your mouth
How to do it - This is my favourite by far. First off, I have to say; unless you have oh... say a half.... WHAT THE FUCK ARE YOU DOING WASTING THC ON SMOKE RINGS!!! Practice with cigs, or some other smokeable, because when you first start, odds are you're gonna need a lot of practice. No need to be wasting hits on smoke rings. Anyway, no matter what you're using, here's how ya do it; The way I recommend learning with is a more consistant technique. Take your hit, and leave all the smoke in your mouth. DO NOT INHALE, just like Bill Clinton. Then open your lips, and form an "O" shape as good as you can. Use a mirror if you want to check the shape. It really doesn't have to be perfect, it just has to be there. Now the first mistake most people make is just opening their mouth to make the O, what you actually have to do is pucker your lips. Not a big gaping hole. The smoke ring will not form if you don't do this right. Basically try to make a "fishy face". Infact the fishy face motion itself could make a smoke ring, but the proper way is what most people refer to is snapping your jaw. Make your puckered lip "O", now drop your jaw as far as it can go without really putting any muscle effort in to it, so it's nice and relaxed. Now simply try to move your jaw upward, it should actually go somewhat forward and upward, which is perfect. Not too hard and fast or you'll just end up with no smoke ring and wasting all the rest of the smoke in your mouth (if you conserve it, you can blow many many many rings of varying sizes from one hit), but not too slow that just a little puff floats up in to your eyes and nose. It's a balance, you'll get it. Just be fairly swift with the snapping motion.
That's the technique I learned with and think is best to learn how to blow a smoke ring with. Once you've got that, or if you wanna jump ahead... now you can try for bigger smoke rings. The way to do this is go back to making the puckered "O", but drop your jaw really just about as far as it can go this time. As far as you want really, the bigger the ring you wanna make. It doesn't matter if it ends up being an elongated O, because this time instead of using your jaw to snap out a smoke ring, you're gonna push it out with your tounge, which relies less on lip shape (off course it will take some experimenting to find what works for you, all I can do is guide). Make a quick sharp forward motion with your tounge, trying to center your tounge in your mouth so it pushes the smoke out evenly. Some people roll the front of their tounge up, some curl it back and use the hump that makes to push it forward, some just jab the tip of their tounge towards the center of the O, either way can work with some practice. Don't get frusterated, it can take a lot of time to get. But one you blow your first few rings, even if they suck and you can only do it one out of every 20 times, you're gonna love doing it for self amusement, and you're gonna find yourself always trying to do it (thus getting better over time) until you're a master and can actually do tricks with the smoke rings. It's also a great way to amuse buddies... and it's fun as hell to watch a smoke ring float and dissapate when you're baked. All in all, I think everyone will find that it's really not that hard. It may be the mark of a veteran, but you sure don't have to be a veteran to blow a smoke ring.
Oh, here's some cool ideas for what to do with your rings once you get better (bear in mind that all of these and even just blowing a smoke ring in the first place will only really work right if there's not much air movement in the room... if the air is still, a good ring can last for near a minute... if not, you may never even make one);
1) Blow a smoke ring, then while it's floating and still a perfect ring, do a "ring kill hit" and just lean forward (or more to wherever it is) and breath it back in to your mouth. Do it kinda slowly for added effect. Your buddies will FREAK. It's also a great way to blow weed smoke rings without wasting THC.
2) The classic, blow a larger smoke ring, and then blow a tiny one through it. If the air is still enough and you got the skills, it's not that hard to blow one large one, then a smaller one through that, then an even smaller one through that.
3) Reverse the last one. Blow a tiny one and then blow a larger one around it.
4) Just see how many you can blow in one hit. My record is 52 perfect rings (of course they weren't huge in size, and I didn't get one on every attempt, but I managed to in one hit... and it was a thiiiccckkkk hit) which I blew for my mothers 52nd birthday... it's become a tradition of mine to blow rings for every year of a friend/relatives life on their birthday.
5) Try french inhaling a smoke ring while it's floating.
6) Possibly the hardest thing to do. Combine blowing a smoke ring and either a french inhale or kill it. If you pop out a smoke ring fast enough, and also blow out a bit of excess smoke at the same time, try and kill the excess smoke back in, or french inhale it.
Well, hope all that helped someone. Only in sobriaty would I ever bother to make a that much of a detailed guide on smoke tricks lol... wish I had some bud. But yeah, best of luck to all Blades at their parlor tricks
Edit: Anyone think I should make a guide thread for this? O.o