To help the bag maintain shape stuff it with paper or bubble wrap before storing. If you've just cleaned the bag, allow it to air dry first. Place your stuffed leather bag in its original dust bag (or natural fabric pillowcase), and then store in its original box, along with silica gel packets to avoid dampness.
Never use newspaper, as the color can transfer.
Do not leave in high heat areas for long periods of time and keep out of direct sunlight and in low humidity. Air your leather bag once every two weeks to prevent mold growth.
You can wrap the chrome or metallic parts in clean, acid-free tissue paper. If your bag will be tucked away for a while, open the buckles and straps to prevent impressions in the leather.