Open all draperies and window shades during daylight hours
Turn on all lights
Open all doors between rooms
The kitchen and bathroom(s) should sparkle
Pets should be restricted from view and eliminate pet odor. Some may be allergic to your pet.
All valuables (jewelry, etc.) should not be visible. Place in locked closet or safe deposit box.
Beds should be made and clothes picked up. Bathrooms should be clean, towels folded and toilet seat down.
Any time you leave the house, leave it as if you know it is going to be shown.