a huge part of my process has been to get everything in the 'right place or right space'. Sometimes this was obvious - all clothes in the bedroom (we had clothes in the living room too - one of exP's bright ideas), sometimes less so - but as clearsomme says finding the right place for things to live is really important.
It's nearly all happened now - though I am still keeping my hairdryer in the living room cabinet & using it in the kitchen - which is all WRONG WRONG WRONG! But once I have the bedroom finished with a mirror in the right place (nearly there) then the hairdryer will be permanently stored & used in the bedroom. Best thing is I can now see how & why the hairdryer set up is wrong which I couldn't do before.
I've also created a 'home office' area on shelves in the hallway & have managed to get all paperwork, pens, tape etc together there instead of being in 5 different places in the living room.
All DC's art supplies are in once place & sub catagorised: paper, glitter, sticky things, pens, paints etc all grouped like with like - easy to find &n easy to put away (no matter how much mess they make in the artistic process)
Not only does this make a huge difference when trying to find things, but it makes it really easy to put stuff away.
And of course the less of it all that you have the easier everything is too.