Being a a collector makes care of e books of great import to me.
Although I haven't gone the route of protective covers yet, the bet way to care for books besides the common sesne thigns like don't eat, smoke, or drink around books without being careful. Also I never loan any of my books, I find other people are simply not careful. I would rather buy a friend of mien a book then let him borrow mine
Everytime I move I make sure I have a room for my books; I have found keepign the room clean, and making it a non-traffic room (no need to hang-out in there) is the best way to go.
Keep them in a cliamte controlled area and keep the temp stable around 60-65 degrees F. Do not expsoe them to light (whether natural or not) for extended periods of time. No Windows is a good diea. Humidity is an issue, your okay between 40-60% .
Some peopel ahve this habit of wanting to look at there collection, I generally don't touc ha book I don't plan on reading.
Add for the love of god, never lay your books open face down!
I have practiced these guidelines and have kept my collection pretty pristine through a few moves. I generally don't have any paperbacks unless a nvoel was first printed that way, I don't buy them otherwise.