The i129f petition evidence of a genuine engagement is one of the most important things that the beneficiary (foreign fiance) must present during his/her interview at the US embassy. The beneficiary must prove that the relationship is real by submitting evidence to the US consular officer. Examples of proof may include the samples of communication, photos of your meeting, receipt of engagement ring and/or letter of intent.
1. Communication. Conversations can be copies of chat sessions, snail mail, messages online or texts, phone call records and screenshots of emails can be presented to the consular officer. If you communicate by viber, skype or fb, you can take a screenshot. If the conversation is in another language, you can translate some of it. Print out about 10-20 pages of your conversations. Do not overdo it.
2. Photos. Create a photo album or a scrapbook of you and your fiances photos. An ordinary photo album is also fine. It does not have to be fancy. You should also place date and location to justify your meeting. During your interview, you will be ask by the CO of when, where and how many times you met your fiance.