I made some cards to help new players with the declaring-of-goods step.
For Sheriffs: Inevitably every sheriff at one point always says the same thing. "Wait? What did you say was in your bag?" Its easy to forget after all. With these cards, a quick glance across the table instantly reminds you of what a player declared.
For Merchants: When explaining the rules to the game, the same two questions always come up. Why cant I put all 6 cards in my bag? Why cant I declare multiple legal goods? When using the cards, intuitively people just automatically understand what can or cant be declared without having to resort to "Caus it is the rules! Thats why!"