Paper prototypes are lo-fi prototypes that can be made in short period of time and that’s why they’re helpful: they’re easy and fast to made so we can include the user again in our process with a usability test(eliminate some usability problems as early as possible). Also, it’s easy for us to come up with multiple ideas of how the prototype should look like.
I’ve seen paper prototypes with a really good drawing and I think this is a mistake because it takes so much time. We shouldn’t be focusing on the aesthetics here, we want a lo-fi prototype that is good enough to be tested.
I’ve seen people making fancy loading screen with animation made with hands and paper. And that’s another mistake, because the user was so impressed with the trick than the product and he said:”Niiiice!”.
We shouldn’t make the user excited because he’s using a paper prototype, and even that most probably he will be, we should make sure we neutralize this excitement by at least not making fancy moves like the loading in the GIF above.
When the user clicks on something, you have to make sure you know what to give him. Prepare the scenarios so well that you won’t confuse him by giving a wrong piece of paper or getting stuck and hesitant what to give him.