We love our trusty labelmaker. For this solution we'll be turning to it again. The first step is (if you're anything like us) to begin by properly reorganizing your numerous storage boxes. What we initially did was put similar things together (like a box of cables.) Turns out this actually isn't the most efficient way to go about doing this. Instead, organize your boxes by things you use the most. Maybe now your magnifying glass will be in the same box as your bathing suit -- that's ok for the system. But this way your most used items can be in the most convenient to reach boxes while the lesser used ones are more hidden away.
What you'll want to do is label your boxes. A numerical or alphabetical system would be sufficient because you won't be relying on them exclusively for finding your items. It's also important to mention that if it makes sense, you can have smaller boxes inside larger ones as well. (Maybe larger boxes get labeled alphabetically and smaller interior boxes get a numerical value as well so A and A.1, A.2, etc...)Once you've finished labeling, head to your computer for the final step of creating an index. We recommend Excel but Google Docs can work as well if you don't have it. Creating a simple chart will work wonders in keeping you familiar at all times with what is in storage. There are a few different ways to organize the spreadsheet and the amount of boxes you have will likely dictate how you approach it. We like to do it visually... as the boxes appear in the closet. Simply block off rectangular sections of color, denoting the boxes. Label the box and list its contents. Now you have an easy visual guide (which is also very easy to update) of all of the things which you have out of sight and out of mind.
(Image: Ikea catalog)