Clean gently and often
Sweep or vacuum (with the beater bar off) to remove grit, which acts like sandpaper underfoot. Use a cleaner made for finished hardwood floors and a microfiber mop. Avoid steam mops, wet mopping, and oil soaps or wax on a polyurethane finish.
Protect from scratches
Put felt pads under chair and table legs, use mats at entrances, and lift furniture instead of dragging it. Keeping pets' nails trimmed also helps.
Wipe up spills quickly
Water left standing on wood can stain or damage the finish and the boards. Wipe spills right away and use mats near sinks and dishwashers.
Watch the sun and humidity
Direct sunlight can change the color of wood and finish over time, so rotate rugs and use curtains or shades in very sunny rooms. Keeping indoor humidity steady helps reduce gaps and cupping between seasons.
Plan a recoat before it wears through
When the finish starts to look dull in busy areas, a screen and recoat can refresh it before the wood itself gets worn. That can delay the need for a full sand and refinish by years.