I believe you need tax returns documents from the last couple of years and two or three recent pay-tubs. One's income level needs to be above poverty-line to fill out affidavit of support. Hope this helps a little bit. Google and find more relevant answers or see a lawyer. Good luck.

its about a year i am here, so i will receive my first year tax returns documents at January and i work 2-3 place on this year and meats their amount required. so ..........

Go for it bro...cheers