Use this form to show they have adequate means of financial support and are not likely to rely on the US government for financial support. Much confusion surrounds the need to submit I751 affidavits and how to write them.We explain and provide an I-751 affidavit sample. An I130 affidavit is a written statement from friends, family members, or associates who can attest to the genuine nature of your marriage. 864 Affidavit of support How to fill out the Form 864 immigration Tips US mmigration with Attorney Jacob Sapochnick Completing and signing Form I-864 makes you the sponsor. In this guide, we will explain who needs to complete Form I864, when to file it, and how to fill out Form I864 stepbystep.