Minor Scales
You really need to start this exercise by reading the post about Major Scales, that post gives a Scale Theory foundation and will help you understand what I am writing about here.
You can create a Minor scale by having a flat 3rd, 6th and 7th. This is a cumbersome approach and understanding the relative Minors is a simpler way to continue.
Every Major Scale has a corresponding ‘relative minor scale’ that shares the same key signature. It has a ‘modal’ name which is ‘Aeolian’. I’ll write a complete post about Modes and you’ll find that also under scale theory. Anyway, you can find the relative minor by starting your scale at the sixth degree. So, for a C Major you will have an A minor. By starting the C Major scale on the sixth degree (which is the 3rd down) you will have played an A Minor. Remember only plat the notes from the original Major scale.
Here is a chart showing relative minors:
