Much confusion surrounds the need to submit I751 affidavits and how to write them. We explain and provide an I-751 affidavit sample.An affidavit of support is required as part of many applications for permanent residence based on marriage or other family relationships. Step 2: In the first paragraph of the affidavit, put the name and personal background information of the person giving the information. An Affidavit of Support is US Immigration Form I-864. Form I-134 Affidavit of Support is an important supporting document for your non-US immigrant visa request. The applicant must use this affidavit to support their claim of residency or being domiciled in Texas. This article will guide you through a sample affidavit of support, highlighting key elements and common pitfalls.