Your first step when you learn how to play air guitar is finding out what air guitar is. Its not just pretending to play guitar there is a lot more to it then that, try to think of it as expressing technique through your movements and making it a visually pleasing experience.
To start with I will give some steps to follow to make your air guitar expericane more enjoyable and how to setup a good environment to that will assist you when you learn how to play air guitar.

Your environment

You will need to have a big room to practice in when you learn how to play air guitar as it can get a little crazy sometimes. Try and clear all large objects out the room and beware of anything overhead as many people have been injured when they first start to learn how to play air guitar. You will not need to worry about the noise created from the air guitar as this is a silent art form.

Preparation

There will be no real need for preparation, but one thing you might want to do is stretch a little and warm up as many muscles as you can because it can get pretty physical when trying to learn how to play air guitar. Any serious injury could mean the end of a great air guitarists career and there is just not enough air guitarists in the world as it is so please be careful at all times.

Fitness

Some people dont realize the rock fitness required when you learn how to play air guitar, but it is very physically demanding instrument. Try to work out at least once a day to maintain peak physical fitness.
You will need to focus most of the time on your arms as they will be used the most when you learn how to play air guitar and remember what I said before be very careful not to hurt yourself.

Pick your tunes

When it comes to picking the music you wish to play when you learn how to play air guitar try to steer clear of things like Frank Sinatra and Britney Spears, as these dont lend themselves well to air guitar. Try and pick something with good guitar riffs and long solos because not much fun when youre standing around waiting, for you cue to start.

Now remember when you learn how to play air guitar use it wisely as the air guitar can be a powerful tool that should not be taken lightly. I think the most important thing you should take away from this is that fitness is the most important asset to an air guitarist and you will need to maintain good physical health. Most people may think that the rock n roll lifestyle is all fun and games but it takes serious dedication to be any good.