I used different color tabs for each section. and i used the plastic ones as they are mor durable. I put topic tabs on the side and information (charts, good info) stuff on the top.
I used purple for structures, pink for geotech, orange for system manage etc, bright green for enviro, dark gree for transpo and blue for water resources.....definately the way to go!
This way all your tabs dont get lost and you know what time is what after using the system for a while!