To care for the finish of the piano, the first rule is to avoid damage. This means that flower vases, drinks, food, or anything else that might spill onto the piano should be kept off. Even books and papers can create very fine scratches, when slid across the surface of your piano’s finish.
For everyday cleaning, wipe your piano with a clean, damp (not wet) cloth, followed by a clean dry cloth. If more stubborn soils do get on the finish, you may try dipping your cloth in a mild soap and water solution before wiping, and then follow that with a cloth dampened in clear water, and then the dry cloth. If your piano has a high gloss, polyester finish, you may use high gloss polish for very fine scratches. There are other, special polishes available for polyester satin finishes.
If your piano has a lacquer finish, again you may use the same treatment of a damp cloth followed by a dry one. You may also use any good quality furniture polish for removal of very fine scratches, and to renew the luster of your piano’s finish.
For cleaning the keys of your piano, you may again use a damp cloth, but be sure that the cloth is just damp, not at all wet.
Also, be careful when you spray anything on your piano, or your piano’s keys. Be careful to keep the spray from getting inside the piano, especially onto the strings. If in doubt, spray it onto a cloth, then wipe it onto the piano. One good source of cleaning products for your piano is www.corycare.com.
There are other products and methods that may be used in the care of the outside of your piano, but they should be handled with care, and usually by professional touch up people, or a professional piano technician.