Well, for one, I would at least attend your local Farmer's Market as a passerby to see if there are any related vendors that fit your niche or product. I've done the Rose Bowl Flea Market (which isn't technically a Farmer's Market) and it was the wrong decision for me. Since people are in the haggling mindset at flea markets, they often are disconnected from the "handcrafted" part of things.
The point I'm trying to make is that researching your local vendor gatherings is essential. The Farmer's Market where I live is about $30 registration which is not much at all in hindsight.
Next, I would create a mock pop up shop setup within your household to see how effective your placements and setup would be. Since you're paying for space, you might as well optimize the presentation early on.
Pinterest has a lot of examples of "pop up shops" to give you ideas on what is presentable in terms or arrangement and theme.
Take pride in your product and don't just lay your product on tables. Wear your stuff, add fixtures that match your aesthetic, and take your brand seriously. Especially if you're preparing to take your business to the next level!
Hope that helps!
