Besides a perimeter expansion gap, make sure the floor planks can move everywhere and don't get hung up on screws for dinette table flanges and entry door threshold, toilet, etc. Where there were screws into the floor, I made the holes in the planks larger so they could also move at those points due to seasonal temp. changes. Don't caulk the perimeter gap as I have seen some do, allow 1/4" +/- and cover with a "baseboard" strip of wood as needed.
Walls and cabinetry are often not in very straight lines and it's a good idea to scribe the cut lines where needed using painter's tape. That way you'll get a consistent even gap.
