The first rule in stainless steel appliance care: no abrasives and no chlorine. The surface of these appliances is a little more delicate and abrasives will scratch the surface and chlorine based products can pit the finish.
The best way to start clean up is plain old soapy water on a nice, soft cloth. This will take care of general dirt and smudges. Follow up with a rinse of clean water on a new cloth.
Just a note: if you have hard water it can leave a residue on your appliances. Polish them dry with a soft cloth after you've cleaned.
For oily fingerprints you do need to get a little tougher. Keep some rubbing alcohol in the kitchen and use a little on a soft cloth polshing with the grain to remove fingerprints.
The alcohol will evaporate quickly and leave you with a lovely clean shine.
I hope these tips keep your stainless steel appliances gleaming! I'm Mrs. Fixit and it's just that simple!