Taxes for Renting Bedrooms

[Derek Luttrell]

Hi everyone, I closed on my first purchase about a week ago (house hacking through roommates), and today my roommate sent me their $900 rent for August via Venmo. 

Rookie question here, but what do I actually need to do to make sure I'm not breaking any laws with that money I receive every month? I know this is likely a better question for a CPA, but I figured I could get some preliminary knowledge on here. Venmo will be their payment method on the 1st of every month. 

Thank you!