The cornerstone principle of home staging is cut and dried: Clear out the clutter. Cleaning and decluttering involves more than just sorting out and throwing away old mail and newspapers. Closets should be emptied out and organized to showcase their storage space. Remove knickknacks and dust collectors from shelves and display areas. Even living room furniture should be edited down to a few major pieces that leave plenty of open space for traffic flow. When organizing your remaining decor, think in odd numbers; clusters of three and five pieces are ideal for creating vignettes, or designed areas within a room. What isn't thrown away should go into storage boxes and put into a rental space if necessary. In addition, every conceivable surface in the house should get a scrub down.
If you're already planning to move, this step of lightening your load will come in handy when you pack up and change houses. But perhaps more notably, cleaning has a nearly six-fold return on a minute monetary investment.