practice a lot,
Also delrin picks like dunlop tortex or clayton duraplex give a very crisp defined attack. This helps keep note separation audible when you are playing fast.
my only other suggestion is to use a metronome. Play some practice riffs along with it. Start at a comfortable speed and slowly increase the tempo instead of just trying to play as fast as you can right away.
1 - Practice
2 - Practice with a metronome. Start at a speed where you can play a passage flawlessly and slowly increase.
3 - When practicing for speed and consistency, don't use distoriton. If you can't play a passage without distortion, you can't really play the passage.
4 - Learn and play as many scales as you can, in as many places on the neck.
5 - Find a guitarist you like and find their lessons on YouTube. If they don't have/offer lessons, find someone who was inspired by them. Marty Friedman, Joe Petrucci, and Emil Werstler all have fansastic lessons available.
6 - Practice
install 8s on guitar
use a lot of distortion to cover sloppy playing...tons of delay/flanger/phaser
move fingers real fast and just make-up scales,...nobody is ever gonna hear you play, anyways
after six months, you'll still suck--go to pawn shop, sell rig and buy drums
hard work, there are no short cuts.
consistant picking technique along with a metronome slow and speed up as you get cleaner. there are thousands of videos on youtube of scales and licks you can practice. control of what you are doing is more important than speed, control of your tone and dynamics and your phrasing. learn how to play, then worry about how fast you can play it. although it is easy for us more experienced guys to say that, as i did not listen to that advice when i was learning - i just wanted to play as fast as possible like john petrucci and rusty cooley (but the difference is both of those guys, petrucci more so, have a seriously strong foundation.. i wanted to skip the foundation and head straight into the speed!! from 16 years old. thats why i'm not a working/earning musician and sit in a miserable office now)
unfortunately i spent the best part of my guitar playing life focusing on speed and not so much on actual control of my instrument, such as knowing the name of every note on the guitar neck and where it fits within any given chord or scale, i.e. having more command in any given situation. took me a long time to also realize my picking was inconsistant i.e. i would hold the pick differently when i sped up vs playing 'normally'. a lot of years wasted. i think it all comes down to wanting it all NOW NOW NOW and not willing to put in the time to get the fundimentals nailed down. the only benefit of my decade and a half of focusing on speed and technique is at least i can pretend i know what i am doing when someone less skilled hears me play, they think i am a serious player. however a real musician would see through all of that
don't do what i did! nail the fundimentals and work your way up. patience, hard work. etc,...