I've sold at craft shows in NYC, upstate NY, NJ & previously L.A., and have done pretty well. I only do juried craft fairs or higher end, non-juried craft fairs, which charge quite a bit for a 10'x10' space and you have to provide your own portable EZ-Up tent & displays. I've also done many of the holiday art (& craft) shows at the various art studios I've worked out of. I've learned from past experience to never do a fair that only charges $25 for a table. This is one of those events where you definitely get what you PAY for (in fair fees) in terms of corresponding demographics attracted to the events, both in terms of vendors and customers.
There is a
huge difference between CRAFT fairs versus street fairs or flea markets. Street fairs are basically events for family entertainment: to take the family for the afternoon. These customers will spend $8 on a sausage hero & a funnel cake, but
not on a quality, hand knitted pair of socks.
At very low level flea markets/garage sale type church bazaars (which is a fancy word for flea market/garage sales

) expect to be talked DOWN on your $8 hand knitted socks as they think they can get a $3 pair of socks from
Walmart. And they can - just not handmade. People have actually insulted many vendors I know by offering a cheap flea market price for something worth 5 times the value. People just aren't there to spend at those, no matter how much they ooh & ah. You're part of the afternoon's entertainment. Or they just want a cheap deal. They have no real appreciation of something being handcrafted. AND the promoters of flea markets & some street fairs, where there is no jurying, will place your high end items right next to garage sale level, similar imported handmade "crafts" made by overseas slave labor, at the booth next to you. Uneducated customers don't understand why they should pay you a fair wage for the same type of item.
If you intend to do many craft fairs, there are a few books on selling crafts that tell you what to look for. Some of the tips are: it helps to attend the fair the previous year before you sell at the same fair, or talk to a vendor who's done it before, or a customer who'd actually buy your level of work. Ideally, you want to do a craft fair that has been around for multiple, previous years, running annually, and has gained a reputation for quality crafts. Watch how they are advertized. It should read, "7th Annual Holiday Crafts Fair," not just "holiday fair," which could be misconstrued as only an entertainment event. And the crafts should be prominently advertized as a big part of the fair's attraction, not tacked on as an after-thought or as an
addition to the entertainment & food, which take priority.
When I attend a fair, even to shop, I always talk to the vendors to see how they are doing, especially if their work is of a similar level or type. I also take a flyer of their advertising other fairs they are doing. Great way to find out where else to sell at without having to have attended the year before, as hopefully they did their homework on the place.

I take a look at who the other customers are. Of course, it really depends a lot on the merchandise available, the advertising by the promoters, as well as the economy at the time, sometimes the weather, and the reputation of the fair. But, if the vendors all look grumpy and unhappy, or there is no turn out, or everyone is at the food & games booths instead, or only the jewelry booths are making money and no one with your type of crafts or price range, you know not to do that one next year.
I've known many vendors who've sold for years at the outdoor, juried, 39th bi-annual, Lincoln Center Crafts Festival. ONE weekend for a booth is $700+, rain or shine,

with no covering other than the EZ-Up tents the exhibitors bring with them. And there have been several times where the whole weekend has been completely rained out and exhibitors have lost more money on the exhibitor fees, hotel & travel expenses than they made. Yet, most vendors I've spoken to who come back each year, are because even if they only did all right that one weekend in June or Sept, they find that the advertising they get by people signing their mailing lists or taking their business cards, more than makes up as buyers deliberately seek them out later, at Xmas time.

This clientele
appreciates handmade, has money to spend ON crafts and they know what to shop for. These are the customers we all want.
One of my goals is to exhibit there.

But, I need a partner who'd be willing to share the booth fee, and has a similar enough style to get approved through the jurying process. Our work has to look cohesive in the one booth, and not like two artists splitting the booth fee. (You're only allowed 4 photos of your work for jurying, plus one of the booth. So all 4 pics have to count, be an accurate representation of your style, be cohesive - no garage sale mish-mash, & be unique enough that they don't have 3 other vendors selling the same exact thing.) I've exhibited at a fair where someone tried to display other items that they didn't present for jurying. (I watched as the promoter whipped out her file copy of the photos submitted) and some pieces were obviously someone else's style & work.

Another booth complained, or the promoters noticed during their walk-through and made them take those items out from selling.
However: on the other end, at higher-end, non-juried craft fairs, I have split a booth and the fees with another artist a few times.

One time, I didn't have enough work ready, so I asked a fellow artist friend at my studio in L.A. if I could take some of her work with me to my fair to fill out the booth. She didn't even have to come with me as I was selling there anyway. And I wasn't asking for any commission or fees, I just needed more work to fill out my shelves, so I didn't look like a fly-by-night amateur.
It turned out to be the perfect arrangement for us, as her work also sold. So I sold her stuff with mine at all my fairs until I moved back to NYC.

She did offer to pay for half the booth fees after that, which helped my costs right there. Her style was a bit different than mine, so it attracted different customers into the booth that might normally walk by, so it was a win for both of us. Then a third artist friend at the studio asked if I would sell a few of her pieces. I said, heck, yes, the more merrier.

Less stress for me to always have enough pieces to sell on my own.
I've noticed that sometimes, people are hesitant to enter a booth or stop at a table unless they see other customers there. And if they see someone buying, they want to know what was the good thing they bought.

So when I was selling my two friends' stuff, it helped bring in people into my booth who may buy one of my pieces too. So, if you have family or friends come visit you while you are selling, have them stand in front of your stuff, while talking to you, like they are customers,

and not just working with you or accompanying you.
Last: make sure you have the Square up app, and have signs around showing you take credit cards. In this day & age, there is simply no excuse anymore why you don't take credit cards. I know many, many vendors who use it and swear by it.

I've bought things where my card was processed with the app. You can even buy an inexpensive Android Tracfone cellphone to plug in the white square card swiper to swipe cards. No need for an expensive smartphone or phone plan. (I used an old Droid 3 that I got off eBay for $30 and activated through Tracfone's "Bring Your Own Phone" plan.) Activate that cell phone for only $8 per month, (a 60 min Tracfone card) only during the holiday craft fair season to process the transactions and toss the phone in the drawer the rest of the year, if you only do sales during the Christmas season.
https://squareup.com/