L.C.
Teach him all of the skills he will need to be a good husband and what to expect in a good wife.
I remember sitting with my dad and him telling me what it really did and didn't mean to "obey" your husband. I remember him telling me what it really meant to "love your wife as Christ did the church." He told me all of the ways men communicate and like to be supported. He told me all of the ways men are good at supporting and areas where they need help. He told me what he loved about my mom. We talked and talked and talked. It wasn't like a lecture. It was conversation. I could ask any question I wanted. No subject was off limits and, as I think back now, some of his answers were hilarious.
Those conversations let me know what to expect of myself and someone else. They, eventually, led me to a really great husband who was all of those things my father described. I know this because I knew what I was looking for. He made sure I did because he told me.
When he asks you questions about what he should be when he grows up, don't say things like, "Whatever makes you happy" or "Whatever you want." Instead, tell him what you see that he's good at, what all his qualities could lead him to enjoy, give him guidance. Even when your young the future can seem uncertain, and it's nice to think that someone has some ideas about it.
Just talk. Talk and talk and talk. Always tell the truth, even the bad stuff, because while he may not like to hear it, he will know you are the one to come to when he needs the truth.
All that talking made the biggest difference in my life and the only things I regret are that he isn't still here to talk to and that he never met the man he taught me how to find.