If I'm a musician and use countless other musicians on my gigs, how do I account for every person? I've only paid a max of $200-$300 to any one individual the whole year.

On your tax return, for your self employed business, you can just enter a total for contract labor help and enter the sum of all payments made to all your musicians for the year.

See steps to enter your business expenses here:

https://ttlc.intuit.com/replies/5802554

If you are referring to needing to prepare 1099 MISC forms for all the help you have hired during the year, you only need to create forms for those that were paid $600 or more during 2018.