Before you go out Gung Ho and buy yourself a guitar, you should probably think first about finding a guitar teacher, who will give you lessons at least once a week. Though, you could learn on your own, it might be easier for someone to show you the ropes and get you started. I have found that many successful guitarists have had at least a mentor or two before they became intermediate or professional musicians. So it would be wise to find one. They are in the yellow pages, at guitar stores, or you might even find one that you actually know (family and friends) or dont know (strangers and sometimes weirdoes!). If costs are a problem, try to stay away from those $30 an hour deals. There are many who offer ones at lower prices (believe me). In fact, I learned for free when I took a guitar class during my senior year in high school. So, in other words, shop and ask around. You will be thankful that you did.
When it comes to the actual teaching, instructors will generally
teach with different styles. He may choose to concentrate
his teachings through music theory, such as tone, dynamics, beats
per measure (meter), full steps/half steps, etc while giving you
lessons on where certain notes are on the fret board and how to
strum chords up and down the traditional way. Others might
just teach you how to read numbers on tabs and how to hit power
chords (3 note chords that are just strummed downward). Some
incorporate a combination of both. Though a few guitarists
may tell you that the former style of teaching is not necessary,
I think they are mistaken. In my opinion, you should,
somewhere down the line, get to understand how to read
traditional, transcribed notation (A, B, C, D, E, F, and G notes)
on score sheets, where the note E is on the 5th string
and 6th strings, how to finger pick, which strings
should be hit on the up strum, and things of that sort. Those
who teach the latter style might not indulge those important
concepts, and just show you how to hit punk rock chords. This
is ok, but Ive always believed in expanding your knowledge
of music and not fixating yourself on just one style. If
you do learn by the latter teaching, go ahead and at least
attempt to study the former way. Try to read as many guitar
magazines and newspapers as possible. Even books that might
be all about piano or Beethovens greatest works could be of
help. The fact is, the more you know, the easier it will be
when trying to understand simple concepts, like manually tuning
your guitar, playing a tune on different frets along the neck, or
figuring out how to listen by ear. Also, it will help in
the long run when creating your own music. It worked out
pretty good for me!