Part A: Cm  Cm  Cm  Cm  Cm  Cm Bb F. x4

Part B: Cm x4.. 

Part A Notes: C Bb G Eb c  g bb c bb c.  Bb F.

Part B Notes: C g C bb g C bb / C g C Bb g c 

Rule: 

You can decide to not return to Part A. 

So the main rule is that if we jam out, you have to bring back the B part clearly before returning to A. 

Possible Structure: 

Part A, Part B

Part A, Part B, Jam in C blues scale, Part B,

Part A, Jam in C blues, Part B,

End on Part A.