Below are just a few other resources that I found helpful when creating the booklet, and are worth exploring when one has more than just a couple of minutes.
Air Warriors - A personal favorite. This is a forum that is primarily dedicated to Naval Aviation, but contains threads on almost every military and non-military topic imaginable. There is a special focus on putting together Navy and Marine OCS applications, flying as an MOS, ASTB test taking, and much more - https://www.airwarriors.com/community/
Officer Candidate School - A blog launched by a man who went through the entire Marine OCS application process, was accepted, and attended OCS only to become injured and unable to return after numerous surgeries. His posts date for years, and it's worth starting at the beginning and working towards the present, as he has a lot of insight and details about the whole process - http://officercandidatesschool.com/
DOD Dictionary of Military Terms - Self-explanatory, but very helpful when scanning through information and uncertain of what something is referring to - http://www.dtic.mil/doctrine/dod_dictionary/