I think one of the key things to do when sorting out and decluttering is to work out how you use things. Some time ago I worked out that if I put something in a drawer, it will never, ever come out again. I then got rid of my filing cabinets, and got shelves and binders and so on. If I can see what I already have, then I am a) much less likely to buy another of the same item because I can't find the first, and b) realise that I never use (and never will use) something and give it away. Other people might really find filing cabinets, files and drawers work much better for them than shelves - the important thing is to work out what kind of person you are. Also, sometimes buying things - shelves, in my case - actually helps a great deal with the clutter by getting it off the floor and tables.

The other big tip is not to try and do everything at once. I am constantly amazed by just how much paper is in my house, since although I work from home I also do most of my work by phone and email. If I look at the giant mess that is my desk and workspace (in a corner of my not-so-huge bedroom), then I despair. If I just take one stack of papers to deal with, then it is doable. I sit in front of the telly sorting out the stack, and resolve to put nothing back in the stack - file it or put it to be recycled - and end up feeling that I have done one decluttering thing well, rather than ten things half-assed and unfinished.