Many board games benefit from improved or upgraded storage of components. Popular techniques for creating better organizers include 3D printing, foamcore, or wood. Many companies or individuals sell inserts for popular games. If you're interested in a technique that is more affordable and a fun hobby, you can also create organizers by folding paper. I learned to do this from a series of YouTube videos. These organizers are durable, (mostly) easy to make, require little up-front investment, and can be customized to the dimensions of your game components and box.
The videos are really the first stop for learning what you're doing. Everything I'm putting here is supplemental tips, and recommendations about supplies. You will also learn that some aspects are more art than science - even with precise measurements, the folding process always introduces some slight variation. Learning to anticipate how certain types of boxes react to different papers, and which dimensions will inflate slightly is gained with experience. In general: Leave some slack, don't try to be too exact at the beginning. Also, you can always remake something that doesn't work out perfectly! (But if you bought some special paper, consider doing a practice box with something disposable).
First, there are some essential tools:
- Paper You want paper with some weight to it, but not necessarily too heavy.
- Paper cutter
- Pencil
- Ruler
- Calculator
- Scissors
Once you start making boxes, you may want to get some additional supplies:
- Scoring tool (mech pencil, etc)
- Bone folder (marker, etc)
- Sticky dots, tape, glue, ...
- Ribbon, other adornments (witch's brew deck holders with washi tape)
- Calipers?
This YouTube Playlist contains nine different videos, explaining how to create various kinds of boxes, dividers, and other organizational aids. They are an excellent resource for learning (or refreshing) any of the techniques.