You don't. I served in the Greek air-force for 17 months as a conscript some twenty years ago which is also obligatory. I couldn't shake the feeling that I was wasting my time at the best years of my life, and the feeling was the same for pretty much most of the guys there. I learned a few things here and there but for the most part it was an utterly boring experience.

The one thing no one tells you about the army is that pretty much 90% of the work done is in management/logistics. A very small percentage is about war per se. There are tons of red tape in the army and there are procedures for everything. So you spend most of your time doing boring stuff that require little to no creative thinking and depending on where you come from, from a point on this becomes miserable. Fortunately by then you're discharged.

Most of the guys who served with me, once they got their bearings they spent the time doing the stuff they enjoyed. For me that was reading books. I read a shitload of books while serving, like one every couple of days. A guy I knew went for wind-surfing every afternoon since we served on an island and the sea was like half a mile from the base. From a point on it becomes like a routine job. You do the army stuff in the morning and in the afternoon spend time on your leisure.