Wear Plastic Gloves
The first basic of storing comics successfully is to handle the comics properly to begin with. Touching a comic book can lead to finger grease stains on the pages of the book. Reading and handling the comic with vinyl or latex gloves decreases your risk of grease stains. If you hope to preserve the comic solely for enjoyment, you can be more lax about gloves. However, grease will increase the likelihood of the pages eventually decaying.
Purchase Mylar Bags
Mylar comic book bags are perfectly sized for the traditional comic book and do not alter the comic book due to any chemical reaction. You can purchase either thick or thin Mylar comic book bags, although the thick are more rigid -- and more expensive -- and are thus less likely to lead to comic book bending. Be sure to measure the comic book and the bag before selecting a bag. Some books are slightly differently sized and bags that are too small or too large can damage them.
Use Backer Boards
Place backer boards in your Mylar bags to help keep the comic books straight and supported during storage. It's important that you specifically buy backer boards intended for comic book storage so that they don't contain chemicals that will interact negatively with your comic book. Make sure the backer board is the right size for the bag.
Buy Comic Book Boxes
Comic book boxes are ideal for comic book storage. They fit standard comic books comfortably, allowing you to flip through your comics with ease, but also keeping the comics from shifting during movement. When you want to store more comic books in the same box, you can opt for longer boxes.
Find the Right Storage Spot
Although you may have extra room in the basement, garage, attic or in a storage unit, you should avoid storing your comic books in places that attract moisture or sunlight. You want a dry, dark, temperature-controlled place for storage, such as a closet or under a bed. If you must store them in a garage or basement or less ideal space, place the boxes on a shelf or skid or otherwise off the floor, both to avoid contact with a potentially damp floor as well as to avoid risking damage in case of flooding. Garages and older houses also run the risk of damage from animals, particularly through the winter months, when the cardboard box and paper of the comics may be used for food or nesting.