I've noticed on group rides that some cyclists highlight turns and other information on cue sheets in different colors. Is there a universal convention for the colors used? (e.g. blue for left turns, pink for right)
I have not seen any convention like that.
When I print cue sheets for the (Maryland) St Mary's Century, I print them so that the color of the cue sheet paper is about the same as the color of the arrows on the road. Orange arrows on the road = orange paper for the cue sheet etc.