I use large letter size envelopes to organize all the documents. My wife loves to take picture, we had taken more than a 1000 photos with a selfie stick, for each trip that we travel together, I choose around 50 pictures to submit. Emails/Facebook messages from friends, work and family about your relationship will definitely help. I have retained almost all of our chat log since the beginning that we met, and I printed all of them out (like 500 pages). Try to print double sided and shrink the font to 8 to cut cost.