Lesson 1: Scales (part 1)

First thing the guitar teacher (from now on known as the 'geezer') got me to look at was the C major scale; apparently its an easy one...

I've drawn up part of the C maj scale below with the most excellent balsamiq ui designer:

thin string on the top of the image

fattest string on the bottom of the image

Short Story:
Looking at image above

1. Little pinkie finger finds the maj note. For 'C' place little finger on the 8th fret, thinnest string, and you will be on C. You are now in 'C' maj.
   
2. Index finger (first finger) finds the relative minor. It is 'always' 4 frets back from the maj. Place your index finger on the 5th fret thinnest string. Your index finger is now on the 'relative' minor, in this case 'A', to where your little pinkie finger is.
3. Pick each note in that pattern above, in the fret position above, and you should hear some 'do re mi fa so la ti' sounds emerging.
4. Enjoy!
   

Longer Story:
You can play that pattern of notes anywhere on the fretboard BUT there is a simple 'trick' to making it easy to find out where you should be playing it for the 'key' (some note grouping from a 'root' starting note / cord) you want to be 'in' - where thankfully & very magically stuff sounds 'nice' together.

Lets call it a black magic get your mojo working trick!
To play in 'C' major you put your little 'pinkie' finger on the 'C' note (in the image above) and you are ready to roll! Easy :)

In this case, in the picture above, the 8th fret on the top (thinnest) E string is the note 'C' (when your guitar is in tune and you are using the standard tuning).

For the next piece of guitar black magic you take your first finger (index finger) and put in on the 5th fret on the top (thinnest) E string.

That magically gives you the 'relative minor' to the note your 'pinkie' finger is on.
Don't worry too much about what a maj / min is right now (I'm not).

So in this case since your little finger, on the 8th fret, is on C maj your index finger, 4 frets back on the 5th fret is going to be on A - which is the relative minor to C maj.

I wish I knew that years ago! Litte finger on the maj then index finger will auto-magically be on the relative minor.

Now from there you move up and down the fret board into other 'groupings' of notes (that have different shapes then the picture above) that also sound 'nice' when played/picked/bashed over somebody else strumming cords in the key of 'C' maj (or it's relative 'A' minor). The geezer called the grouping in the image above 'position one' but I've also seen it called 'pattern six' else where.

Next part of lesson 1 (coming later) was other patterns of notes that make up a C guitar scale and where to play them to stay in 'C'.

Phew. I'm knackered after writing all that. 

Time to stop writing and play :)