<prompt> Human: Hi everyone, I do face painting, by myself, and usually get paid in cash.This Easter I worked at a church event and was expecting to get paid by check. However, it was poorly planned no lines, no cutoff time and I ended up staying later than my previously agreed hour to paint the rest of the children that were in line. This part I dont care so much, working an extra hour for free. But, when I finished, the man who was supposed to pay me said the treasurer left for the day and he would mail me a check if I email him an invoice. I did this and now the treasurer is asking me to mail her a W-4 form. Ive done a W4 before for regular jobs, but I dont know how it works if you have your own business. Im worried because I didnt register my business or whatever youre supposed to do though I dont think I make enough money where I would have to do that anyway? Should I fill out his W4? What will she do with it? Will she take take out of the money I asked for? Should I cut my losses? I dont want to get in trouble for having this little business. Im clueless. EDIT: my apologizies, it was a W-9  <response>: Just try explaining the situation to the treasurer, surely she will understand that you just have a skill you like to use to earn a little side cash and not a full legitimate business. 