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. 3. Clearly and legibly print your name at the top of the Affidavit form exactly as it appears on the identification document you have selected.4. Clearly and legibly print your name at the top of the Affidavit form exactly as it appears on the identification document you have selected. The I864 Affidavit of Support is a signed document that a sponsor signs in order to accept full financial responsibility for the sponsored immigrant. The petitioner in question must fill out Form I-864 Affidavit of Support when petitioning and sponsoring an immigrant. Form I-134 Affidavit of Support is an important supporting document for your non-US immigrant visa request.