When you know someone is coming by to tour your home, turn on all the indoor and outdoor lights – even during the day. At night, a lit house gives a “homey” impression when viewed from the street. During the daytime, turning on the lights prevents harsh shadows from sunlight and it brightens up any dim areas. Your house looks more homey and cheerful with the lights on.
Do not use scented sprays to prepare for visitors. It is too obvious and many people find the smells of those sprays offensive, not to mention that some may be allergic. If you want to have a pleasant aroma in your house, have a potpourri pot or something natural. Or turn on a stove burner (or the oven) for a moment and put a drop of vanilla extract on it. It will smell like you have been cooking.