[Mike Simonds]

Assume A gains 4 yards on 1st down... After U spots the ball, R tells H "2nd down", H tells B "2nd down", B tells L "2nd down" and L finishes up by telling R and U "2nd down".

This gets everyone on the crew used to making verbal and visual communication between every down.

Also, in our 5 man mechanics the B is responsible for calling strength of formation. The B, H and L then pick-up their eligible receivers from this call. In our association the B will punch towards either the H's or L's side of the field to let them know how to cover the formation.

These should be good basics to work-on for your crew.