Or does someone know of pictures of the correct way to do it? Also, could it be that the strings slip around on the saddles, and is there a trick to keep them from doing that?

I have the classic problem with the B string going out of tune, which is obviously it slipping on the plastic nut. But there is a problem with the other strings going out of tune and that's what I'm asking about.

Also, will leaving your guitar out of the case when you aren't playing make the strings go dead more quickly? I live about 5 miles from the ocean and was wondering if that had something to do with it.