Buy a mouse pad. A slick desktop, or, worse yet, a slick desktop covered with dust, is the worst possible environment for a mouse. A mouse pad is the best.

Mouse pads are rectangles of 1/4-inch or thicker material designed specifically to give your mouse good traction while preventing the weight of your hand from flattening the ball on the underside of the mouse. They'll help keep your mouse clean and provide a consistent surface that makes it easier to control the screen pointer.

Mouse pads are available for as little as $4 at the checkout counter of your computer retailer. Or you can spend $25 to $30 for a designer mouse pad embossed with a picture of your favorite cartoon character. Either one will do the trick. But be careful of some colorful designs -- the printing process can make the surface of a mouse pad too slick for comfortable use. Always run your hand over the surface of a pad before buying. It should have a slightly grainy feel.

Consider a wrist rest. Keyboards are responsible for most of the repetitive stress injuries that have plagued office workers since desktop computers became popular business tools. But heavy mouse use can take its toll on the muscles and nerves of your hand, wrist and arm, causing numbness, stiffness or shooting pains.

The best way to keep your mouse arm healthy is to take frequent breaks, stretch your muscles and flex your arms and hands. You may also be able to minimize strain on your wrist with a mouse pad that contains a wrist rest. The padded rest keeps your wrist from bending repetitively. You may barely notice these motions, but over time, they can cause damage to the tendons and nerves in your wrist.

Keep your mouse clean. When you first got your computer, your mouse undoubtedly moved quickly, precisely and effortlessly. But now you may notice that it's "skipping," or that you have to pick it up and put it down a few times to get it moving at all.

Your mouse could be wearing out, which happens eventually. But it's more likely that your mouse is just dirty and needs cleaning.

The mouse is subject to more contamination from dirt, spills and dust than any other part of your computer. Every time it rolls across the desktop, the ball picks up tiny particles of grit and grime. It deposits this dirt on the tiny rollers inside the mouse casing that transmit horizontal and vertical movement signals to the computer. As the dirt builds up, the rollers no longer make firm contact with the ball, and the mouse starts to behave like a drunken sailor.

Cleaning a mouse is easy. First, unplug the mouse from the computer (make sure the computer is turned off). Then turn the mouse upside down, and you'll see a circular cover with a hole that allows the ball to touch the desktop. Remove the cover by turning it, and let the ball drop into your hand. Clean the ball with soap and water or alcohol and let it dry.

Now, look inside the casing. You'll see two wheels situated 90 degrees to each other. There's a good chance those wheels will have a solid streak of caked-on dirt. Your job is to CAREFULLY remove the dirt without damaging the wheel. Some people use a cuticle tool or small screwdriver, while others just scratch away with a fingernail. It's tedious work because the wheels are spring-mounted and tend to slip away from your finger, but with a little perseverance, you can do it.

When you're through, shake out the mouse so that the dirt falls away, then replace the ball and cover. When you use it again, your mouse should snap to attention. If you're concerned about damaging your mouse, ask an experienced friend or retailer for assistance.

While it's almost impossible to keep a mouse from picking up dirt, you can help matters by keeping your desktop free of dust. Always use a mouse pad, and don't forget to wipe it clean from time to time.