I was told to use the disposable leather cleaning wipes to clean and condition my leather furniture every 4 - 6 weeks. Due to the build-up of dust on the furniture, you may have to use several to begin with.
look up Lexol...they make a whole line of leather care products
Go to your local auto supply shop for leather cleaning products. Just be sure its not mold that has got onto the leather. If so you need to really clean it well using Murphy Oil Soap and several clean rags changing often.
I was told by furniture company to nit use auto cleaning products