1.
Select a key. The beginning of a blues progression, written as a Roman speech that I followed from numbers 7, 17, determines the sound of the whole melody.
2.
Play four actions, or stacks, repeating the first note of the progression. If you choose to start with an A chord, play A7 for four actions.
3.
Change to the IV7 chord for two actions. In a blues progression in A, the IV7 chord is D7.
4.
Return to the I7 chord for two more steps.
5.
Continue with the V7 chord for two measures. In the example, the V7 chord is E7.
6.
Go back to the I7 chord for the last two actions in the progression. This complements the 12-bar of progression.
7.
Repeat the progression as desired. A single 12-bar progression is usually too short for a song, but several interconnected progressions form the basis of many blues and rock and roll songs.
Tips and warnings
Blues consists of a simple, repetitive structure. Like jazz music, it can include improvisation, but the musician’s creativity is expressed in the basic structure. The 12-bar blues progression is a common structure that forms the basis of many blues songs. It’s easy enough for beginners to learn, but with enough room for variety it will be useful throughout its musical career.
Source:danspela.com