How To Write A Marine Recruit Address On An Envelope . Using the app, you can send pics in a note that includes a postage paid addressed envelope for your recruit or sailor to write back. Write the full rank, the full name and then the branch for active military personnel. Letter Two Letters from Marine Corps Boot Camp Marine Boot Camp HQ from marinesbootcamphq.com Include with envelopes, stamps, address labels, and a pen. These can be white, manila, or matching the paper your resume is on. Write in apo or fpo for the city.