This is a great question. If you need to be creative, then I would say that you should pick a few themes on the life of a solider and creatively tease these out to make your points. Let me give you some examples of themes.
First, you can write about the fear of death. I am sure any soldier in the front line fears this. You can write about the psychological fear, the emotional fear, and even the physical fear. You can also write about the fear of not seeing loved ones and the fear that takes place when fellow soliders die.
Second, you can talk about the smell of war. You can talk about not showering, not changing clothing, and the smell of death and bodies decay. You might also write about the smells that this solider misses.
Third, you can write about boredom. These soldier at times do the same things day in and day out. The waiting must be hard.