Thou Shalt Not…
…get sloppy in thy practice. The way you practice is the way you will play. Develop good habits now while you still suck. Then, when you’re a better player, the habits you developed early on will pay off in a big way!
…run before you can walk. The secret to playing well fast is – get ready for this – to first play well s-l-o-w-l-y. If you can’t play that lick perfectly at 60bpm, you have no business playing it at 200bpm.
…sacrifice emotion for technique. Speed and slick sounding licks are great. There is a place for them. If that is the kind of player you want to be, more power to you. Just remember, though, that a good sequencer can take your place.
…ignore technique. This is the flip side of the emotion/technique argument. Having great technique and learning (gasp!) music theory will not interfere with the emotional aspect of your playing – unless you let it. Don’t hide behind the tired excuse that “all that technique gets in the way of emotion.” That’s a sad excuse for not building your chops. Face it: it’s a cop out. The truth is you’re just too darned lazy.