Download this document (or make a copy to your own drive). Save it to your drive. From here on out do the following on here: 

1. Track your income, whenever you make money date it, describe what the session was, the amount you made, and then put it in the INCOME column. 

2. Track any expenses of things you buy ( sd cards, camera gear, uniforms, etc,.) date it, describe it, the amount you paid, and then put that same number under the correlating column.. was it fees? equipment? did you advertise? etc,. 

3. At the bottom of the document if you see a red number then something isn't adding up. Make sure you're tracking EVERYTHING. This helps when it comes to taxes.