I am an artist with a Masters degree, and I make some income on my work, but I don't have a 1099. How do I write off my art-specific expenses?

YOu don't need a 1099-MISC. As far as the IRS is concerned, you earned that money while self-employed and "in business" for yourself. So you will report all business income and expenses on SCH C as a physical part of your personal 1040 tax return. The IRS expects you to keep your own detailed records of all business income/expenses and use those records to complete the SCH C. You will have to use the self-employed version for that.

https://ttlc.intuit.com/questions/1901340-where-do-i-enter-schedule-c 

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