Sooner or later – and it really doesn’t matter whether you are into rock, blues, country or any other style of guitar music – you are going to need to know where the notes are on your fretboard. In effect, you will need a fretboard map. Sure, you can get by for a while just reading tabs and playing along with jamming tracks, but once you start playing with other people you need to be able to exchange information, and tabs just don’t cut it. For one thing, they are only useful to other guitarists, and for another they rely upon everybody else having the same tuning as you.
At first glance, learning what note each fret creates on each string seems like a pretty daunting task. After all, there’s over a hundred of them. Or are there? In fact, everything is a whole lot simpler than it first appears. Just follow me carefully for the next few lines and you’ll begin to see why. I’m going to assume that your guitar has standard tuning, which means that, starting with the 6th (thickest) string the tuning is E A D G B E.
Here’s the first – and in many ways most important – thing to remember: the notes on the two strings tuned to E are exactly the same and in exactly the same position, although they are an octave (eight notes) apart in pitch. So, for example, if you hold down the 6th string at the third fret you will be playing a ‘G’, and on the other side of the fretboard, on the 1st string, you would also be playing a ‘G’ at the third fret. What’s more, unless you are playing a classical guitar, the manufacturer has very kindly inserted a little dot at that point to help you find it. He has done the same thing at the fifth fret (‘A’) and at the seventh fret (‘B’). So, without even reading any further, you already know where to find 12 notes, since you already know what the ‘open’ strings are. Not bad for a few seconds work, eh?
Okay, so what happens if we start at the tuning peg end of a string and go fret by fret towards the body? Well, it goes like this: every string, on every fret, follows exactly the same sequence; it’s just the starting point that is different. So, your ‘E’ strings read as follows: E F F# G G# A A# B C C# D D# E. And look what you find at the second E – more little dots to let you know that the sequence starts all over again, how easy is that? It can’t be all that difficult, because you now know where more than 30 notes are and you’ve hardly started.
Now, here’s the truly amazing bit: just as the notes up and down the strings follow the exact same sequence, so too do the notes across each individual fret. Is that cool or what? It means that, once you know what that sequence is, you can quickly work out what any note is anywhere on the fretboard. Now, before we go any further, I want you to look at the sequence of notes in the paragraph above and see if you spot anything odd. Got it? Yep, everything proceeds in half steps – indicated by the ’sharp’ # sign, except for the notes ‘E’ and ‘B’, and that’s because they are themselves naturally occurring half steps. To get a clear picture of this, look at the keys of a piano. ‘E’ and ‘B’ are the only two notes that don’t have a black key separating them from the next note as you move up the keyboard (from left to right). And because one of our strings is tuned to ‘B’ this has a minor impact on what follows.
To make this easy, I’m going to start with note ‘A’. Travelling across the fretboard, fret by fret, the sequence of notes is A D G C F followed by the same notes one half step higher; i.e. A# D# G# C# F# and finally the two half steps, B E, are tacked on to the end. So the full sequence is A D G C F A# D# G# C# F# B E. And you can remember this by using a simple and stupid mnemonic. For example, imagine a gold rush starting because someone called Arnie found some fool’s gold somewhere. The tabloid headline the next day might be Arnie’s Dodgy Gold Creates Fever, repeat for the sharps and then add B E (Before Evening?).
Now let’s deal with the fly in this particular sugar bowl; the B string. If we start on the 6th string at the fifth fret, what word is that? If you said Arnie’s you have grasped the first principal already. So, the note on the ‘A’ string will be Dodgy, on the D string it will be Gold, on the G string it will be Creates and on the B string it should be Fever – but it isn’t, it’s a half step lower, or E. Which is why the next note starts the sequence all over again and is an A on the second E string, just as it was on the first. This happens every time you pass the B string. No matter where you are in the sequence, the note on the B string drops by one half step and the sequence then continues from that point. To help you grasp this, remember that the note on the next, last, E string is the same as the one you played on the first E string.
It’s a lot to take in at first, I know, but there are visuals available that can help you learn and remember how this works. You can find a very handy and free fretboard map here. There are also a number of other very cool tools on the same page, including a free chord book. Help yourself 
