I'm going to post this journey, it may be helpful to the right people.
I was a 14 year OS in the Coast Guard, left because I wanted to pursue other professional interests. At my last duty station, I knew I was not going to renew my contract, however, I had three years left to complete the current contract.
I started thinking about my next step and had a few years to prepare. I enrolled in APUS to work on my bachelors in environmental science (I wanted to work in the natural sciences), the popular military college was a good experience, I recommend it, great option for certain paths. I used Tuition Assistance to pay for those years, free (but limited) money that allows you to save your GI Bill. At the time of my separation I had only one year left of school, so I activated my GI Bill (3 years of benefits) to finish at home. During my last two years on active duty I started getting involved with my local U.S. Fish and Wildlife branch conducting ecological surveys as a volunteer research assistant on my days off, this was really important to gain valuable experience for grad school applications, network (letters of recommendation, references), and resume building. They offered me a seasonal job too once I left the CG. Once I finished my bachelors, I applied for grad school. Got into a great California State University geography science one year program. I had two years left on my GI Bill, so tuition was well taken care of and I got $3,000 BHA. I am just about to graduate with the Master's degree and got an offer for full-time work with the U.S. Fish and Wildlife as a GIS/Cartographer. I got all of my benefits back and years served by working for the feds again, but as a civilian employee this time.
For the OS's out there, we get a lot of training in geography science, whether using charts, digital maps, or SAROPS (ArcMap), and geography jobs are not really pitched to us as potential new careers outside active duty. We get a fair amount of training in spatial science and this correlates to a new'ish profession called Geographic Information Science (GIS). Every major industry, feds and state's are using GIS software technologies to crunch various types of data, create maps and analyze scientific data. It could be a viable option if you prepare yourself in the right way.
It was a huge leap to leave the CG at 14 years and try something new. I took about 2 years after leaving to be in a position to qualify for what I was looking for, in all, 5 years of school and a lot of volunteer hours. I got lucky in some regards, but it took a lot of hard work. Hope this helps some people looking at building their qualifications for what comes after the CG.