Step 1: Preparation

Take up any old floor coverings and remove pictures, curtains and as much of the furniture as possible. Cover anything left in the room with dust sheets.
Hammer down any protruding nails in the floorboards with a hammer and nail punch as these will rip the sanding sheets. You must also fix down any loose boards and fill large gaps with pieces of new board.

Tip: To stop dust going over the rest of the house, make sure you have everything you need in the room and seal around the internal doors with masking tape. Open any windows and exterior doors.

Step 2: Coarse grade sanding

Work diagonally across the boards with the floor sander. If the boards aren't stained and in good condition, start with the medium grade sanding sheets. Otherwise, start with the coarse grade sheets.
Work slowly across the room, overlapping each strip and keeping the machine moving all the time to stop ruts forming.

Tip: Crisscross the room in the opposite direction to remove deep stains.

Step 3: Medium grade sanding

Once you have sanded away the worst of the staining, swap to the medium grade sheets and sand in the direction of the boards.
Finish off with the fine abrasive, again working up and down the boards.

Tip: Empty the dust collection bag regularly to prevent it bursting with the weight of the dust.