Clear a Path
Keep your front walkway (right to the street), porch and driveway clear! Periodically sprinkle a layer of sand or salt over them. Put a rubber mat by the front door or a container to hold wet umbrellas and shoes.
Let in the Light, especially on dull winter days
Open all blinds, shutters & drapes on every window (unless the view or outdoor scenery is particularly undesirable). Turn on every light in the house, including appliance lights and closet lights. If your room is particularly dark, you can add some spot-lights behind chairs, directed into the room to brighten things up.
Sparkle isn't just for the holidays
Wash all windows. Clean cobwebs and dust everything including ceiling fan blades, and light fixtures. Bleach or re-caulk dingy grout in tubs, showers, and sinks. Polish chrome faucets and clean mirrors - especially in bathrooms. Clean out the refrigerator; you know it needs it. Make sure your floors are clean and vacuumed - if you have plush carpeting, vacuum in one direction. Empty trash and recycling bins every day, including bathrooms and under the sink.
The temperature inside should be warm and cozy, so buyers will want to linger longer. It's best to turn the heat up a degree or two warmer than usual and then set the temperature at normal to prevent the heat from kicking on when the buyer is present (some HVAC systems are loud).
Be Moody and set the stage!
Rooms should appear warm, cozy, and inviting. Add a couple of wine glasses near a wine bottle on the coffee table; toss a throw blanket across the arm of your sofa. Set the dining room table for dinner with your best china. Put a tray on the bed or bedside table with a couple coffee cups, napkin, and reading material. Turn your bathroom into a spa by hanging plush robes on the door, place washcloths and towels in baskets, arrange a grouping of soaps, lotions, and shampoo.
Evoke a sense of summer in winter! Place vases filled with fresh flowers around the house.
Have soft music playing throughout; light jazz or classical music is always soothing. If it's the festive season, nonreligious holiday music is a nice touch. Don't turn on a commercial radio station; instead stream your tunes from a computer or tablet, to have continuous music playing without talk/commercials. Mute the ringers on telephones and turn off answering machines.
No scents makes sense!
Many people are allergic to certain scents and deodorizers, so don't spray the air or plug-in air fresheners. Don't spray perfume in the bedroom for the same reason. It also makes people wonder what you're trying to cover up!
If you're going to bake cookies or simmer spices in water on the stove, make sure you are offering cookies as well. You don't want to lure people into a room only to have them disappointed that there aren't any cookies!
If you have an antique chandelier that's staying with the house, put a note out that tells the age of it perhaps. If your basement stairs are steep, attach a card to the railing that cautions buyers to watch their step or their heads.
If there is something of value that is not included in the sale, but could be negotiable, placing a note saying "Not included in the sale" could makes a buyer want it and you can negotiate that later to your advantage.
Plug indoor lamps into a timer to automatically turn on at in the evenings as the sun is going down. Make sure the outside of the house is well lit. Consider using a motion detector to turn lights on when needed.