The natural way is to put the binder away like a book. The advantages of this way are the same that storing books this way give. But here is why I don't like it - the pages are heavy, and the tension on the rings causes problems for the rings, the pages, and the cards (the ones in the positions where the shift causes warping of presses them against a ring or something). Also, dust collects on the top row of cards where they are wide open to the elements.
Storing them horizontally has its advantages, but I worry about the weight. and in order to stack them, you have to put something in the binder to raise the cover to level.
I've thought about securing the binder shut with a strap or something and then storing them binding up. this distributes the weight of the page evenly on the rings, and it solves the dust problem. But it requires a modification to the binder. Another thought for storing the binder binding up would be to have a rod sticking out of the rack and then hang the binder on the rod. This would have the advantage of the weight being on the metal ring holder, But the tabs are in the way with most binders.
Any ideas that don't require special binders or binder or storage modifications?
Generally, the condition I look for is: 1800s-1929 - G and up (1+)... 1930-1951 - VGEX and up (2.5+).. 1952-1967 - EX and up (5+)... 1968-1978 - EXMT and up (6.5+)... 1979-1994 - EXMT/NM and up (7.5+)... 1995-present - NM+ and up (8.5+)