Depending on where he is going and how much room he has ,most have very little especially the Marines,they still live in condemed barricks right here in the US, some when deployed live in a tent with others, some have little plywood like shelters. I just kept cards,letters, news from home and assorted snackes and things. Many have access to computers and can comunicate easily. Some however depending on their "job" in the military may only have access to a computer once in awhile. When My son was in he was too tired to walk to the chow hall so I sent lots of food he could prepare with hot water, oatmeal, raman noodles etc.It really depends on their likes.
It is important to support those who don't get much in the way of support, My son asked me to write to a girl that didn't have support, now three years later we still wright letters at least once a week and she has been to my house once, She has become a dear friend to me. And I know my support means the world to her. I am glad you will give this young man a link to home....