I took (am taking) lessons. I've gotten a few books and DVDs as gifts but they don't help me very much. You could teach yourself with tabs and stuff but anyone can learn individual songs using tabs. I would strongly recommend lessons just because you get someone else with you who knows how to play and learning in person is much better than a DVD where you can't ask questions or anything.
I have to second the lessons idea. I don't know how to play guitar, but lessons were by far the easiest way to improve when I used to play other instruments in school. And I echo what Teddy said about being able to learn individual songs by tab alone. I've had a guitar for a few years and try to teach myself a song every now and then, but I feel like I'm simply parroting the page and not really learning anything. If I weren't so lazy and cheap, I would definitely go the lesson route.
Best way to learn is lessons. And shop around. Then find some approved books and practice on your own time as well. If you're serious, learn theory. If you just want to jam around the basement for fun, just learn tabs and noise. I'm self-taught and developed some bad habits so get with a knowledgable instructor and go from there.
I taught myself. Books with pictures of the chords are nice. Play with other guitarists and pick up tips. Lessons are good as long as they don't focus on music theory the entire time.
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I've taught myself so far, but I really wish I had taken a few lessons. However, you could probably learn a few of the chords and get comfortable switching back and forth, stringing a few together, etc. before you start shelling out money. Hope you decide to try it and stick with it though, can really be a lifelong thing.
I don't take lessons, and I'm decent at guitar, and pretty good at bass, but my dad is also a very good guitar player and a lot of my friends and my dads friends play, so I'm around musicians often. You probably could teach yourself, but you need to at least know someone whos good at guitar to pick up tips here and there.
Well, my Dad had taught me acoustic guitar when I was growing up and so, I knew how to read sheet music. Knowing this made the process easier when I picked up an electric guitar. I was pretty decent at playing classic Metallica and Slayer in high school, but around my junior year in college I stopped playing completely. Hadn't bothered to pick it back up again, seeing how my garage metal band days were over. Besides, I was always more of a drummer.