To do this I bought a black index card box from Paperchase, it has a magnet to keep it closed and metal hinges. I decorated the top with some washi origami paper. I made divider cards by cutting cardboard to the right size and decorating with more paper. The recipe cards are 6×4 index cards from Staples.
For years I have been scribbling recipes in moleskin books but as I didn’t start out with any system other than writing things chronologically it has become quite hard to find a recipe again without having to search through the whole lot. The solution was to do the logical thing and have recipe cards, I don’t know why I didn’t think of it before! Now I can sort by breakfast, lunch, dinner, and cake, and reorder things as I go. The system is working well so far :)