Just because you're holding your guitar doesn't mean that you're playing it, and just because you're playing your guitar doesn't mean that you're practicing. There is a real difference and it needs to be acknowledged if you want to improve your level of playing skill. Some people say they have spent the entire day practicing their guitar when in reality, all they've done was sit in front of the TV all day eating cheesy poofs. The sad thing is that they really do believe it was practicing since they had their guitar on their lap next to their cheesy poofs all day. Most of us know someone who does this and we may even be guilty ourselves.
In order to truly improve your skills you really need to avoid any distractions, no TV, no food, no friends and no phone. Just you, a guitar, an amp and maybe some reference materials. Speaking of amps, keep the distortion turned down. Remember, this is practice, not playing. The distortion will only hide your mistakes. You need to hear your mistakes clearly so you can correct them.
If you're a beginner you might want to practice basic guitar scales or guitar chords. Make sure you have the necessary reference material handy so you don't spend your time doing things wrong. Keep in mind that what you practice is reinforced so if you're practicing your scales wrong, then you've not only wasted your time; you've also reinforced your mistakes.
So what should you practice? Since I've never heard you play I can't tell you what you need to improve on, but I can make suggestions to make your practice more effective.
Don't turn your amp up to 11 and play every solo you know. This is playing the guitar not practicing the guitar. It might be fun and a great way to blow off some steam, but it won't improve your skills.
Don't let practice get stale. You need a variety of things to keep your mind from wondering. Practice your scales for an hour then work on chords or music theory. Mix it up. Just be sure not to over do any one area because you'll get bored and at that point your practice won't be as effective.
Don't just go through the motions. Part of a good practice session is finding problems and figuring out solutions. If you're having trouble fingering a particular chord, then analyze the problem and try to find a solution. You might think that your fingers are to small or weak, when the reality is that you only need to improve your technique. When I first learned to make barre chords I had a rough time making all six strings sound clear. Now I can make them all sound clear with very little effort. I would also add that I don't believe my hand strength has much to do with it at all.
Use a metronome when practicing. This will help you improve your timing and make everything sound better.
Learn the basics first. If your beginning guitar you should know and understand the basic relationship between chords and scales. This will help you to better understand the logic of the chord patterns when you learn songs and what scale you should use to solo over top of that particular chord pattern. Check out my lesson "Guitar Scales and Chord Triads" at "www.guitarmetal.com" for a visual reference that might help.
Pick a time of day to practice when you feel most alert. If you're groggy or unfocused, your practice efforts will be compromised. You might work better if you break up your practice session into several times throughout the day. For example, maybe practice an hour in the morning and a couple hours in the evening. You know when you feel the most alert so take advantage of those times.
Be prepared with things to work on. Don't just sit down and noodle around for a couple of hours. Before you sit down you should already know what you're going to work on. This will help maximize your time.
Edward D Cupler is the owner of guitar lessons website guitarmetal.com Offering free guitar lessons to beginners and advanced students. Ed is also the owner of Digitalgreys.com