I have an entire 6 foot bookshelf full of paper. It is sorted by size, kind ( vellum, patterned, foils, handmade, basic cardstock, etc.) This is for full size sheets. My " scraps" are stored in pizza boxes labeled by color. On my work table is an old cheese box that holds smaller " scraps". This way if I need a small piece of a certain color - such as a scrap of yellow to make a sun - it is right at my fingertips, and I don't cut up a full sheet.