I have yet to meet a player who doesn't want to know how to shoot a basketball better. And I think that's a good thing. Shooting is one of the most important basketball skills your players can learn. You never know what shot the defense will give you, which player will find themselves open and in position to shoot. The more of your players who know how to shoot a basketball, the more likely your team is to score.
Coach the game long enough and you will see all kinds of basketball shooting techniques - some picture perfect, others incredibly awkward-looking. Although on occasion these awkward shooting styles will work, a player is highly unlikely to develop a consistent, accurate shot without good basketball shooting form.
It is terribly important that in practices, good basketball shooting form is enforced. Muscles perform movements that they are used to doing - i.e., players train their muscles to perform the same movements over and over again. It's called muscle memory - after a while, after the basic form of how to shoot a basketball has been drilled into the muscles, every time they begin the shot, the muscles automatically perform the appropriate motions.
In a game situation, players need to act and react without thinking, and that means they need to take the open shot the instant it presents itself. Their muscles need to perform the movements they've been taught automatically, that have been drilled into them in practice. Teach your players good basketball shooting techniques and then reinforce them every practice, and by game time they will have improved their consistency and accuracy.
These are the major points to emphasize when teaching your players how to shoot a basketball. If you are lucky enough to be dealing with players who haven't developed bad habits yet, then get them setup properly using these points and have them practice over and over until proper shooting form is ingrained.
If, on the other hand, you working with a player who has developed some bad habits, you likely won't need to change all these points, but probably will need to focus on a few. Watch them shoot and choose which aspect will help them the most. Focus on that until they learn it well, then add the next. Don't try to change everything at once because they won't be able to do it.
If you do have a player with particularly bad form, a player that needs a lot of work, focus on the points that are most important to good form - check out my page dealing with the three most important aspects of good shooting form.
And Good Luck!