House Cleaning Secrets Revealed

Don’t use water, it will ruin them. Use leather cleaner.
References :

This may seem funny, but a friend of mine who has a very rare Cadillac says to use Dove soap. Let it sit in water for a day or two so as to make a paste. Then use this to clean your seats. After that portion is done use a damp towel to “rinse”. Then dry everything off and use Pledge (Regular) furniture cleaner to protect.
References :
http://www.cadillacforums.com/forums/cadillac-deville-1985-2005-including-1985/136402-best-leather-cleaner.html#post1472661