How do you differentiate between denominations of currency?
I usually don't carry cash, (that way I don't have to end up dealing with all different amounts of change, having to dig it out etc.) When I do, I fold the bills different ways. It's a bit different with coins though. Coins are all different sizes and textures, (at least here in the US.) I really only have to carry quarters for my laundry, and cash when I'm on trips, so I don't deal with it that much!