I usually make "pocket map" for quick reference. I'll scan my map (or use an electronic copy) and print it on an 8 1/2 x 11 piece of paper that can then be folded up and put in a sandwich-sized ziploc to be carried in my pocket along side my compass:



This typically provides a map that covers approximately a 10 x 13 km of land (1:50,000 map). Additional information (park provided trail maps, trail book descriptions, additional maps, etc) can also be printed on the flip side and, if want more info on-hand, I can always just print a second or third page.



I find that by doing this I have the information I want on-hand quickly, but I also carry the full size map in my pack for when (or if) I need it. For example, I don't often transcribe the UTM info on to my pocket map so if I want to figure out exactly where I am using my GPS, I'll pull out the full map. It's also there if I require a larger view of things, like when triangulating my position or something.

I hadn't really thought too much about the redundancy aspect before, but I guess this also would mitigate the risk of not having a map due to loss or damage.