Step 1 Learn These Two Scales.
A Natural Minor
A Harmonic Minor
Use a finger per fret i.e. use your 4th finger for notes at
As they are very similar it's easy to get confused between them.
A Natural Minor is in effect a C Major scale from A to A ( Aeolean Mode )
A Harmonic Minor has a G# instead of a G but is otherwise the same.
I recommend trying to keep your first finger on the third string 1st fret ( G# ) as much as possible when practicing the harmonic minor as the most common mistake is to play the open G note.
Try running up and down from open A to open B and back with your first finger firmly locked on that G# note.