Most popular music, whether it's rock, blues, or even country, is based on a few common scales, so we're going to start with those. Specifically, we'll look at the major and minor scales, and the major and minor pentatonic scales. These are fairly simple guitar scales that are extremely useful in a wide variety of musical contexts.
First Things First
Let's make sure we have some basic terms down. A scale is a sequence of notes based on a specific chord. The scale begins on the tonic, or root, note. For example, all scales in the key of C will begin on the note C. This can also be called the '1' note, and the notes that come after are referred to by their position in the scale. Looking at the C Major scale, the note D comes next, so that's the second note, followed by E (the third), and so forth.
The Minor Pentatonic Scale
The minor pentatonic scale is probably the most useful scale you'll ever learn on the guitar. It's also one of the easiest beginner guitar scales to learn. This one scale is the basis for literally thousands of songs, and you shouldn't go any farther in the lessons until you can play it smoothly, in all positions. We're going to begin in the key of E because that uses open strings, which makes it a little bit easier to start with. First of all, there are only five tones in the minor pentatonic ('penta' = five; 'tonic' = note). In E, these are: E, G, A, B, D. It looks like this:
E -------------------------------
B -------------------------------
G -------------------------------
D ------------------------0--2--
A ---------------0---2----------
E ------0---3-------------------
_____0 3 0 2 0 2
Make sure to pay attention to the suggested fingerings: third finger on the third fret and second finger on the second fret. Also, as you learn guitar scales it's never too early to start working on alternate picking: picking the notes in an alternating down, up, down, up pattern. To do this, down-pick the first E by picking toward the floor. Then up-pick the G by picking up toward the ceiling. Down-pick the open A and up-pick the B. Finally, down-pick the open D and up-pick the E on the second fret to finish. Try to make your hand movements as small as possible. It won't be easy, but it's a critical skill.
That's it: the E minor pentatonic scale. Of course, you're going to want to use the higher strings also, so now we'll extend the scale to two octaves, with an extra G on top to finish the pattern. It looks like this:
E --------------------------------------0--3---
B -------------------------------0--3----------
G ------------------------0--2-----------------
D -----------------0--2------------------------
A ----------0--2-------------------------------
E --0---3--------------------------------------
Notice that the notes simply repeat from one octave to the next. Practice playing this scale until you can do so smoothly and with alternate picking (down, up, down, up, etc.). Focus on picking in a slow but steady tempo, and remember to keep that right hand movement as small as you can.
Once you can play figure 2 comfortably, you're ready to come back down the neck. It looks like this:
E --------------------------0--3---3--0-------------------------
B ----------------------0--3-------------3--0-------------------
G ----------------0--2-------------------------2--0------------
D -----------0--2----------------------------------2--0--------
A ------0--2-------------------------------------------2--0----
E --0---3--------------------------------------------------3--0--
Notice that we repeat the high G: that's just to make the picking pattern a bit easier. Practice until you can play this entire pattern smoothly and with proper picking. Even simple guitar scales can sound great if you play cleanly, smoothly, and with confidence, so practice until you're happy with the way this scale sounds.
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