I can help you on how to indicate the employee's job on an invoice, macsmusicschool.
You can turn on the Track classes feature to track the employee's job by lessons, by departments, or any other segments in your business.
For more details about class tracking, you can check out this article: https://community.intuit.com/articles/1776444.
Let me know if you need anything else with managing your business in QuickBooks Online. Just add more details by posting a comment below.