you could tell him how proud you are of him and how strong and brave he is.. and how you fully support him and cant wait for him to be home. and reassure him that everything is good at home and that you can be trusted (if its an issue) and that youll be thinking of him constantly. write a few things that you know would make him laugh and draw him cute pictures...send him pictures of you if you can.. lol naked might be best..
Tell him how much you physically miss him. Be desc<x>riptive, but not over the top. Keep in mind he will be sharing it with his fellow recruits as well as showing your picture that goes along with it. It's a "this is what I have at home waiting for me" pride thing.
My heart longs for you my love, days are so empty without you. But I'm very lucky to have you in my life. You add all the beautiful colors to my life. I love you baby. Missing you a lot. <br />
P.S I have a surprise for you! ;)<br />
I say this to my love when he is not around.
A photo of yourself and sow how sexy you look and show him watt he miss and tell him what he miss
I miss you loads! ;)