1. Change the strings regularly - there is perhaps no more important aspect of playing a musical instrument than that of maintaining it properly. Guitar strings wear out with regular use and even more quickly become coated in grease and dead skin. So it is imperative that you wipe the strings after playing and also change the strings as often as needed.
But how often do strings need changing? Well, if you only play your guitar a couple of times a month then you will probably get away with a couple of sets of strings per year. But if you play in a band a couple of times a week or more then you should renew the strings at least once a week. And forget the old wives tale about boiling strings that is for fools and practical jokers; fit new strings every time.
2.Play what is required, not what you like – Just because you have mastered that tricky right hand tapping technique does not mean that you should try to use it at every opportunity. Instead, concentrate on what feels and sounds right for the piece you are working on. It might not be as self satisfying to play five notes where you could have squeezed in fifty, but it can often be far more effective - and remember that you will always get the chance to impress your mates on another song.
3. Practice effectively – Do you have a regular practice schedule? If not, then you should develop one! Your guitar practice should include different techniques, slow playing, fast playing, rhythmic playing, etc. Don't just play what you enjoy playing during solo practice sessions, but instead remember to devote some time to the stuff you find difficult.
4. Play with the band, not over them – Never turn your amp up to eleven and expect the rest of the band to join you. Not only is it a recipe for tinnitus and premature deafness, but it will quickly get you replaced by a more considerate guitarist. An effective guitar player will be listening to the whole band, not just him/herself, and if the guitar sounds too loud the effective guitar player will turn the volume down to a level that matches the rest of the band! If you think you might be guilty of this then try listening objectively to the whole band next time you play and ask yourself if it sounds well balanced.
5. Be original - Don't just copy your guitar heroes. Of course it is natural and essential to actively learn the chops of your favourite players, but don't just copy them verbatim; instead you should try to mix and match the techniques you have learned to develop your own original licks.
6. Keep an open mind and ear – Just because your favourite player uses a Marshall stack or a Mesa Boogie combo, and plays a Fender Stratocaster or a Gibson Les Paul doesn't mean that you have to do the same. All of the best player's sounds are unique and exclusive, and it goes far beyond the equipment used. Think of the different sounds produced by for example Jimi Hendrix, Hank Marvin and Eric Clapton – they are all Strat players but all sound different and apart from each other.
7. Enjoy yourself – the fact is that successful guitar players actually enjoy what they do; think of Eddie Van Halen leaping around the stage with a wide smile on his face. I'm willing to bet that the reason he became such a great player in the first place is because he actually loves what he is doing. So when the time comes, go out and enjoy it!