Select a variety of index cards, in different colors and/or sizes, depending on the number of flash cards you want to make.
Use markers or crayons to write the problems or words on one side of each card. For example, write "4 + 4" (or some other problem) if making math flash cards.
Flip the flash cards over and write the answer to the problems on the opposite side of the card.
Decorate the flash cards with stickers. If making math cards, use multiple small stickers to signify the numbers.
Use a single hole punch to punch a hole in the center or corner of the left side of each flash card.
Thread a book ring through the hole and close the clasp to keep your handmade flashcards safely organized.