I DESIGNED A NOSE GUARD FOR MY DOG AND GAVE IT AWAY. NOW 500 DOGS WEAR ONE

Summary from the TLDR Founders newsletter

People wanted SnoutCover's dog nose guard but couldn't easily print and assemble the free design themselves. After trying to help them find local printers, its maker opened a shop. The first order arrived 16 days after the website went up. A year later, it had 395 orders across 16 countries. Customer photos led to better straps and custom fits. The design remains free, while the shop sells finished covers. If you give away a design, check which requests are for changes to the file and which are asking you to make it.