well, I've been a little off from the computer these last 2 days and I'm glad Ben gave you a good advice as well, so, let's see
A very good drill which I'm always working with would be chromatic exercises. Assuming that you have 4 fingers at your left hand, you can invent a lot of fingering combinations. Here would be some that I like:
1432 4321 4312 4123
1342 1243 4213 4312
1243 1432 4312 3214
The numbers belong to each finger at your left hand (1 - index, 2 - middle, 3 - ring finger, 4 - little finger)
alternate pick these vertically - starting from the low e string towards your high e string. Shift one fret up when you reach the high e string and continue from there towards the low e string and so on
you will develop a tremendous finger independence as well as good alternate picking skills.
Now, the idea is that you can create a lot of these combinations by yourself - the harder they are for the fingers, the better they'll work your finger independence and warm you up very well
Start slowly, until you can build your muscle memory - these are not obvious exercises so they shall be a little more difficult than others.
Please let me know if you have any trouble with them and of course, if I can further help you