This "jam session" is an Gb7 chord played over and over for you to get down all funky and play some blues.
"Stab" away with the left hand chord only
in time with the music.
Add Gb, Bbb, Cb & C
in the right hand.
Tip: Always play a Cb after the C.
Play any notes from the blues scale.
Tip: Always play a Cb or Db after the C