
Work through the Dominant 7th scale by starting on the low E string and move up the available notes in steady steps. Once you have exhausted all the notes on each string move on to the next string starting on the lowest note progressing up.

You can position this anywhere along the fretboard. By changing the note you start on and following the spacing of this scale progression exactly you can play in just about any key. The first note you start on determines the key you are playing in.
As an example if you start this scale at fret 5, you will be playing in the key of A. If you start this scale at fret 7, you will be playing in the key of B.
Practice this scale moving up and then practice the scale backwards (down), start off slowly and eventually build your speed up as you gain confidence.