One thing that makes a good guitar player is finger dexterity and clean sounding notes. It is important as a beginning or intermediate guitarist to practice techniques that will increase finger dexterity. I will share some techniques I have used and still use today to improve finger speed and dexterity.
Here is a real basic finger exercise. It can be a little tedious, but be sure play every note clean and in even time. Play it slowly, your cheating yourself if you rip through it haphazardly. The purpose is to strengthen your fingers and you'll have to start slowly to do that. Speed up after you can play it well. Play this all the way up and down the neck.
This next exercise is similar, only in a different pattern. Be sure to use all four fingers and watch out for fret buzz,
that annoying buzzing sound that occurs when playing notes sloppily.
Here is a simple riff I made for you to practice over and over, up and down the fretboard. You can make up your own as well. After you get these down, keep playing them. Play them while your walking around the house, on the web, watching TV or eating. Gradually play these faster as you get better at them.
Once you have built up your finger dexterity you can now start attacking scales and modes. Shown below is a simple mode.
Now lets take the mode and 'play it out': Notice the pattern used. You can apply this to any and all scales and modes.
This works excellent for building speed and dexterity.
You can also play this backwards. I like to play this while warming up my fingers. Always be sure to warm up your fingers before you begin a long 'jam session'. Warm up with these exercises listed above, or with some scales. I have heard that some guitarists will massage their hands and run them under luke-warm water before playing to loosen up their fingers. Personally, I think that's a little extreme but you should try it and see if it works for you.
Not all guitarists are concerned with speed and clean sounding notes. Some are just happy with having a sloppy style, and that's fine. But basic exercises like these should be practiced by all guitarists, even the sloppy ones; because they will reap great benefits if done correctly.