I started giving private softball lessons this year and get paid in cash. What forms do I need to file and claim this income for my 2019 taxes?

[JohnW15 · Accepted solution]

You'd need to file a Schedule C, Profit or Loss from Business, and a Schedule SE, Self-Employment Tax, if your net earnings from self-employment were more than $400.

In TurboTax, type Schedule C in the Search box and then select the Jump to link. This will take you to where you can enter any income related to your self-employment. You may first be asked some general questions about your business. After you answer them, you’ll be taken to the Let's enter the income for (your line of work) screen where you can enter this income as Other self-employed Income. 

If you owe Self-Employment Tax based on your net income, TurboTax will compute it for you.

[JohnW15]

Also, please see the TurboTax FAQ on Estimated Tax Payments:  <a rel="nofollow" target="_blank" href="https://ttlc.intuit.com/replies/3301891">https://ttlc.intuit.com/replies/3301891</a>