What happens next?

How to use a document organiser
Purchase a document organiser.
The size will be determined by the documentation that you intend to keep. If you only wish to store receipts, you may choose a smaller document organizer rather than if you are going to store larger pieces of paper and documents then you should probably choose a large document organiser.
Decide what categories you want to include. Once you have decided on your categories, then you will need to label the tabs on the separate compartments.