Completely depends on how you are selling. Usually you should have a hangtag. If you happen to be selling from your own website direct to consumer, then I would say it’s not absolutely necessary, but if you are selling wholesale, retail at a tradeshow, or have a booth at a craft show, then having a hangtag is a nice addition.
A lot of the time you’ll notice that the hangtag is a very simple shape with the logo on the front, and that’s about it. I always recommend including your website but not necessary if you don’t want it. Hangtags are an excellent surface for any additional information you want your customer to know about you. A hangtag could include a paragraph explaining how the company started, sketches showing how to use a complicated piece, a barcode to offer a customer a discount, etc.
Now that your garments are labeled correctly, get out there and sell!