A simple rule to a profitable work space is get rid of anything that is not directly related to the business you are currently running.  Binders, business cards, and materials from your last job or  business do not belong in your day to day world.  If you must keep them, fine, but put them into storage. 

Become friendly with your garbage can and recycling bin.  Why are you keeping little pieces of paper, pens that don't work, snack food wrappers, magazines you don't read, broken and / or outdated electronics, and various other crap around?  Throw it away.  Recycle it.  Don't lose important information and stuff in the piles of trash.  Dusting once a month is a good idea as well.  Constantly sneezing because the dust bunnies are attacking you is not a wise decision.

Have a place for things.  Where do you put your receipts so they are not crumpled up all over the place?  If you have an order from a client, where do you find the paperwork?  Where do you keep your business cards so you can find them when you need the information?  You don't have to have a perfect filing system, but at least if you have certain areas / boxes / shelves for your regular things you can find them without wasting hours and losing business.

If you are currently working in chaos, set aside one evening or weekend and go on a cleaning mission.  See if you can get a neat freak to help you out and see what you can get done in a short period of time.  Grab some trash cans and get busy.  The feeling of accomplishment and freedom you get from cleaning your space will completely reenergize you.

"Cleanliness is the cornerstone of discipline and the trademark of success."

            Wes Fessler