Stainless-steel appliances need a little more than just a wipe down with a wet sponge.
You don't need harsh chemicals to get the job done, though. If you have vinegar and oil, you have all you need. It's eco-friendly and takes just a few minutes.
You would think this would leave your appliance feeling oily, but if you wipe it down properly, the appliance won't feel oily at all. I didn't believe it either until I tried it. The results are great and the oil and vinegar combination wards off fingerprints, so you don't need to clean as often.
How to treat your appliances with oil and vinegar
Step 1: Wipe down your appliance with a cotton cloth dipped in white vinegar. Be sure to rub in the direction of the stainless steel's "grain." If you look closely at your appliance you will see tiny little variances in the color of the stainless steel. These color differences form lines going in one direction. This is the grain. When you clean your stainless steel, always rub in the direction the lines are pointing.
Step 2: Dab another clean cotton cloth in olive oil or mineral oil and rub along the grain. After you're done, wipe down the area with a clean cloth.
These two oils don't yellow when they dry and they leave a protective coating to prevent moisture damage. I live in a humid area and my stainless steel tends to get little rust spots if I don't treat it.
When your appliances start to look a little rough, just reapply. How often you reapply depends on how much your appliance is used, but the treatment should last a few weeks in most homes.