If you file a tax return for any reason, you must report all your income, no matter how small (cash, or the fair market value of items you receive in barter). You might not get a 1099 if your income is below a certain level, but you are still required (on the honor system) to voluntarily disclose your income and pay tax, and if you are audited and the IRS discovers that you have not reported income, you can be charged the tax plus a penalty for not reporting it. (Of course, only about 1% of taxpayers are audited. Tax are mostly still on the honor system.)
This activity might be a hobby or a business. Some factors are here.
https://www.irs.gov/newsroom/hobby-or-business-heres-what-to-know-about-that-side-hustle
https://www.irs.gov/newsroom/know-the-difference-between-a-hobby-and-a-business
If it is a hobby, you report the income as miscellaneous other income. You can't deduct any expenses. You pay income tax on the income.
If it is a business, you report it as self-employment income on schedule C. You report your gross income, and you can deduct business expenses if you have adequate records, although I'm not sure what your expenses would be. You pay income tax and self-employment tax on the net profit.
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