I had no transition experience. I was in the reserves. I went into the commanding officer's office. The paperwork was already prepared. I was told, “Sign here. We don't need to tell you where the door is because you already know.”
I'm going back a few decades now, and a lot has changed since then, thankfully. In my personal case, I just left. I wasn't made aware of any services or benefits that would have been available to me at the time.