Frequent oil changes are very important for preventive maintenance, as old oil can become diluted and contaminated which can cause premature engine wear. Before beginning, make sure that you have all the tools that you need, and lots of rags or newspapers for spillage. It's best to change the oil when the engine is warm because hot engine oil flows better, but be careful to avoid hot parts. Lifting the car on a hoist, ramps or axle stands - to provide a better access to the underside of the car, to ensure the car is level, or the sump drain plug is in the lowest point. Put a draining container under the drain plug and unscrew the plug, holding it in the sump and unscrewing it. Let all old oil drain, shaking the container as necessary. Once drained, clean the drain plug and its threads, fit a new sealing washer and refit the drain plug, tightening it to the specified torque. The oil filter is at the base of the sump, on the right hand side, and it may need a cover removing in order to get at it. Reposition the draining container under the filter, slacken it and unscrew it by hand, being ready for spillage. If using a filter with a plastic body, use a strap wrench to prevent any damage to the body. Cylinder Block Clean the cylinder block around the filter mounting, and check to make sure the rubber sealing ring hasn't stuck. For models with a renewable filter element replace the old element, clean the casing and fit the new element with the sealing ring coated with clean engine oil. Screw the filter into place and seat tight by hand. For models that have a plastic casing, tighten it to the specified torque after hand-tightening. Remove the oil drain container and tools and lower the car. Remove the dipstick and oil filler cap, filling the engine with the proper grade and type of oil, adding it slowly until the level is halfway on the dipstick. Start engine, watching oil pressure warning light, and check for leaks about oil filter seal and drain plug. After a few minutes, turn off the engine, wait for the oil to settle and recheck the dipstick level adding more oil if needed. Finally, dispose of used engine oil in an environmentally safe manner and following environmental regulations.