In the past I tried to use colour coded files and folders - ideally only 3 - red, yellow and green.  It worked for me as I could see at a glance what I needed to grab.

I did try using coloured post-it notes at one point - ie anything on pink was urgent, yellow was waiting for a reply and so on but this system fell down when my stock ran out and we were only allowed to order yellow.

Currently I have to use what I can get.  We have to order the cheapest and this is usually a buff coloured one.  We also are having to re-use as much as possible so they do tend to get quite tatty.

In magazines I see advertisements for stationery items with a secretary sitting in a perfectly tidy office surrounded with coloured coordinated files and folders and dream..............