Oh wonderful! I hope it'll print ok, thank you for sharing with others. There's a few other mushroom critter zines (mushroom newts or "mewts" and mushroom octopuses) should you ever need more critters. The name puns aren't as good there though, I don't think I'll beat mothrooms haha.
https://drive.google.com/drive/folders/1U4Z6IBNwyJDftDXX6-Q6-vmRV8CD4mSr?usp=sha...
Here is the pdf. Essentially you would print double sided, flipped on the short side, and create 4 sheets of paper, that once lined up, folded, and bound, turn into the final booklet.
I've already shipped the little guy, but I did get one photo beforehand, and I included that as well so you can marvel at the cuteness you created