I would like to colour code a shape file containing road polylines to represent the heaviest flows of traffic. The shape file contains attribute data linked to each section of road where road traffic counts were taken (count points). There are 2 fields that contain Road names and a unique count point ID.
The second shape file contains point geometry representing the location of each count point. The attribute data contains various fields including traffic numbers along each section of road, road name and a corresponding count point ID.
How do I A) best combine the 2 sets of attributes to then be able to B) colour code the busiest roads in the darkest red?