Declutter, Depersonalize, Pack, & Clear All Surfaces!
If there is no need for it, pack it or sell it. Organize whatever is left to the best of your ability. This calms buyers.
Remove personal photos & mantras. You do not have to replace them. In many cases, nothing on the wall is as good as a painting or piece of art.
Whatever you are not currently using, pack up! For example: take a look at your closets and pack up clothes that are out of season or that you haven't worn in a long time. This will "loosen up" your closets and will make them feel like there is more room. Do as much of this as possible in all areas of your home.
Think "nice hotel". When you go into a hotel room you think, "Wow this is nice." But in reality, all of the hotel furniture is cheaper than your own, yet it "feels" nicer. Why? Because there is nothing on the surfaces or out of place. The same thing will happen to buyers who walk into a home with clear surfaces! Don't leave anything sitting out and come up with quick storage solutions for things like liquid soap that you use and normally leave sitting out. When there is a showing, try to store that under the sink for the showing.