What a clear cover protects against

A clear cover takes the damage a working surface collects and the table underneath does not. Rings from a cup, ink bleeding through paper, the fine scratching that a laptop foot leaves over months, and the heat mark from something set down without a coaster all stop at the vinyl. It matters most on the surfaces that cannot be repaired: a printed woodgrain finish or a veneer cannot be sanded back the way solid wood can, so a mark is permanent. Because the sheet is clear, the grain or colour you chose the table for still shows through.

Thickness, and what it changes

Covers here are 1.5 or 2 millimetres thick, and the difference is more noticeable than the numbers suggest. The thinner sheet is lighter, easier to cut down and settles flat sooner after unrolling. The thicker sheet resists puncture and indentation better, holds its shape rather than following every irregularity in the surface beneath, and lies flatter over the long run. For a desk that takes a laptop and paperwork, either works. For a surface that takes weight in one spot or the point of a pen through a single sheet, the thicker one is the safer choice.

Measuring, and whether to cover the whole top

Measure the surface itself rather than the furniture, and decide whether you want the cover to reach the edges or to stop short. Running it to the edge protects the whole top but leaves a visible rim, and on a table with a moulded or bullnose edge it will not sit flat over the curve. Stopping an inch short sits flatter and reads as less obvious. Sizes here run from 14 by 24 inches for a small work area up to 42 by 78 inches for a full desk or dining table, and one cover in this range is round.

Getting it to lie flat

A cover arrives rolled and keeps the memory of the roll for a while. Unroll it and leave it lying flat, ideally in a warm room, and it relaxes on its own over a day or two. Warmth is what does the work, so a cold room slows it down considerably. Do not try to force the curl out by folding it back the other way, which creases the sheet permanently. Once it has settled it stays flat, and the corners are the last part to give up the curve.

Cleaning and what to keep away from it

Wipe a clear cover with a damp cloth and a mild detergent, and dry it rather than letting it air dry, which is what leaves streaks on a transparent sheet. Keep solvents, acetone and abrasive creams off it, because all of them cloud vinyl and the clouding cannot be polished out. Lift the cover occasionally and clean underneath as well, since dust that works in at the edges is visible through the sheet and will eventually be ground into the surface it was bought to protect.