1. Start by finding your maximum speed that you can play the exercise. Increase the speed of the metronome to the point where you can just barely play the exercise. Any faster, and it would be a sloppy mess.

2. WATCH your hands at this maximum speed. Figure out what you're doing wrong. Are your fingers tensing up? Are you pulling your fingers too far away from the fretboard? Are your two hands not working together in a synchronized way? Is your picking flying all over the place? Take notes of what you're doing wrong!

3. Slow the metronome down to the point where EVERYTHING disappears. At this point, you want to be doing everything totally PERFECT. Make sure that you are playing COMPLETELY relaxed (this doesn't mean play weak, it means stay relaxed.) Then make sure that your hands are playing in synch.

4. Gradually increase the metronome, and whenever you see any mistakes start appearing, focus on eliminating those mistakes one at a time.

5. Think, think, THINK about how you can make your movements more efficient, more effective, faster, easier, smoother, cleaner... I've given some examples above, but there are many more things to keep in mind.

That should get you started. Go through this process until you reach the maximum speed that you started with, and then find your NEW maximum speed!