Clear the closets, walls, shelves, rooms and drawers. everything should be half empty to create the impression of SPACE! Pack your favorite stuff away, get a storage locker, move it to the new home or stack the boxes in the basement.
Clear each closet to give ample space for clothing (yes the buyers look in your closet) and stash away all but your best outfits.
Each room should have a single major decoration and only 1 or 2 other minor decorations. The same goes for furniture, a singular signature piece, the bed, couch, table, ect. and only 1 or two other pieces.
Empty the shelves of your cupboards, drawers and bookcases to show off all the space available in the home. Odds are the buyers considering your home are looking for an upgrade, they are already cramped and they need to see your house will give them the space they need.