I was reading this BGG page:

https://boardgamegeek.com/boardgame/4550/1000-blank-white-cards

And it looks like a fun game to play, especially with some jumbo index cards.

Some ideas for a good ruleset based on what I read in the forums:

• At the beginning of the first game, each player makes 6 cards and leave 4 blank cards. All cards get shuffled in. On subsequent games each player makes 4 cards, chooses 4 cards from archive, and also inserts 4 blank cards.
• Each player draws 5 cards from the deck
• The starting ruleset for the game is draw a card, play a card
• If you have a blank card in your hand, you can turn it into a new card. New cards should have a name, a drawing, a type, and a description.
• The game ends when there is no cards left to draw
• Each card is one of the following types:
  • action - do what it says and then discard it
  • thing - modifies a player state (add/subtract from score score or giving a special ability). Place in front of you (keeper) or another player (giver)
  • modifier can be played on things to change them - such as give them armor, make them bald, fast, green. Could change values of the card it is modifying
  • new rule - change how the game is played
• Point values for things can range from -100 to +100
• Actions are usually discarded after play
• Cards can have suits (I am thinking colored stampers) and colors which makes it so they can be targeted by other cards.
• No skip turn cards - seems to be the least fun cards