Tipping is a personal decision and it greatly depends on the level of service you received. However, as a general guideline, it's customary to tip between 15% and 20% of the total cost of the service for a job well done in the beauty industry.

For instance, if your nano brows procedure costs $500, a 15% tip would be $75, and a 20% tip would be $100. If you're extremely satisfied with the service, you might consider tipping more.

Remember, tipping is not obligatory but it's a nice way to show appreciation for the artist's skill and effort. It's also important to note that many artists in the beauty industry rely on tips as a significant part of their income.

In the end, the amount you tip should reflect your satisfaction with the service and your personal budget. Always ensure to show your gratitude, whether it's through a monetary tip, a heartfelt thank you, or a positive review.