[quote=@Katakuri]
[@Tortoise] Our characters are in a caravan, meaning they probably would need mounts and such unless they want to walk. Am I allowed to make something to attempt to have it incorporated into the world? So, Cricket has a mount for her size? 
[/quote]

I vote that Cricket rides an actual cricket.

But to answer your question: you don't need to fill out a sheet or anything to give your character a mount. You can just say, IC, that your dudette is riding on one. Most of the writing and worldbuilding here will be done IC- I'm not the type of GM to make you fill out sheets for everything you wanna do. You can just give her a mount.