What documentation should I include in my DTV Visa application regarding financial support and freelance work?

Hello everybody,

I am applying for my DTV in Hanoi right now. I am going the soft power route with a cooking class. I have no online income but do have bankstatements that reach the requierments and a sponsorship letter from my parents that will support me with a monthly budget. I also do work in Germany as a freelance socialworker from time to time, but I do that like once a year to save up money for the rest of the year (wouldnt want to show proof for that income, because back then I didn't meet the financial savings requirements if that would be a problem). What is the best way of putting this information into the online application for the DTV Visa? Do I put in my freelance status if I am currently not working and my last pay was months ago? Where do I attatch my sponsorship letter to proof I can financially sustain myself? Any answer would be highly appreciated