My own experience with craft fairs is limited, but I do talk to all of my friends who do them. My best advice this year is less is more. If you only sell one thing, then it is okay to have 50 choices, but if you have a variety, just show a few of each to make it easier for people to decide. The most successful booths I see allow the shopper to focus and choose quickly. Over the last 3 years, I have seen the average price of sold items at shows go down. To come up with something of an impulse buy at shows, find what you can make quickly with materials you already have. For me, that means these fabric coasters. I am using up my scraps and making sets to sell at the one show I will be doing. My pattern ($2 on Craftsy) comes with the template for the packaging that you can customize and print on your printer. I think branded packaging makes your booth look more professional and gives your products a higher perceived value. What do you make that seems to work as an impulse buy at shows?