Note: Before doing any work on your dishwasher, turn off the power at the circuit-breaker box.
If you start noticing water around your dishwasher, check your gasket for cracks or deterioration. If the gasket is damaged, remove it by unscrewing it or prying it out with a screwdriver. Cut a piece of the old gasket to use as a guide at the hardware or appliance store; if the store doesn't have an appropriate gasket, you can order one from the manufacturer. Before installing the new gasket, soak it in hot water to make it more flexible.
If your sprayer isn't functioning properly, it might be clogged. Remove the sprayer, and soak it in warm white vinegar for a few hours to loosen mineral deposits. Then clean out each spray hole with an awl or a pipe cleaner.
If you notice rust on your dishes, check the dishwasher rack for nicks or scratches in the plastic finish. If you notice an area where the metal is exposed, repair it as soon as possible with a plastic coating material or a marine-grade sealant. Clean and sand the area before applying the new coating.
If your dishwasher isn't level, it could leak. To check, open the door, and place a level along the edge inside the dishwasher. If the dishwasher isn't level, you can raise or lower either side by adjusting its "feet," located on the front. You may need to remove an access panel to make the adjustment.