The goalkeeper decides where he throws the ball between two squares to begin the first 1 vs 1 duel (1); B vs D in the picture. B must keep the possession (2) and pass teh ball to his teammate with the same colour A in the other square (3).
A receives and must keep the ball possession too (4) till the goalkeeper’s calls the color of the 3rd attacking man between the players E and F, (red one in picture). A then pass forward to his new teammate (5) who must keep the possession (6) and finishing (7).
F and the player in the second square can try to win the ball back and finish too. If one of the defending players D or C wins the ball, the goalkeeper immediately calls the color of the 3rd attacking man.