neat (carefully arranged with everything in the correct place): He always keep his desk extremely neat.
tidy (clean and with everything in order): He showed me into a tidy living room.
ordered (carefully organized or arranged): He led a very ordered life.
orderly (a neat and logical way): The vehicles were parked in orderly rows.
in apple-pie order informal (in perfect order): Their house was in apple-pie order, with nothing out of place.
uncluttered (not containing unnecessary things): We keep the room uncluttered, and it makes it seem lighter and bigger.
shipshape informal (tidy, neat, and in good condition): We have to get this house shipshape.
trim (neat, tidy, and well cared for): We have rented a trim villa for the summer.