Whats The Best Way To Clean Leather Bound Books How To Clean Old Leather Bound Prayer Books?

How to clean old leather bound prayer books? - whats the best way to clean leather bound books

I came into the possession of two old books, one of the Missal of 1962, the other a prayer book. The Missal has a clear plastic over them. Carefully separate the plastic cover to soak, and I in warm soapy water, remove the plastic sticks and is slightly yellowed but still in good condition to protect the missal. The missal itself is preserved in very good condition, almost complete, except for the cover very sticky. It seems bound black leather. Perhaps years from the remains of snuff, I think. All ideas on how to clean it the best? The prayer book is just OK by the way, had no protection. What can I use to shine? Thank you .....