What to be aware of when you take the photographs:
Cloudy days are actually quite nice for photos. It eliminates the problems of sharp shadows that often make viewing a photo difficult. A very dark day or dark cloudy evening might not be the best, but a regular cloudy day when the sun is high works well.
Clear out the clutter and depersonalize. Remove family photos, evidence of a pet, or messy bookshelves. Take off hanging towels from the kitchen, take everything off the refrigerator and only leave one or two things on counters.
Look through the viewfinder with the camera, imagine it as a print in your hand, notice what is showing on the outer right, left, top, and bottom of the screen.
Try different angles and look at the room from different corners to see what will probably look the best. You can always crop out some unwanted items/area in the periphery.
Which rooms? Some people include a minimum of a front photo, 4-10 inside images, and maybe one of the backyard or the back of the house. Inside photos generally include the kitchen, main living area, bedrooms, and bathroom(s). Consider including any rec. room, family room, or bonus room. Ultimately, it is your advertisement and you should choose the photos that best compliment your property.
Inside photos: Take these photos during the daytime. Turn on all lights. Keep ceiling fans off.