If I could teach a boy to be a man, I'd tell him to play football. Or to take up theater instead, if he preferred (just not simultaneously in the end-zone, unless he's looking for a 15-yard penalty).
I'd tell him flowers are always, always good. Sending them for no reason at all? Even better. And when he's calling the florist, to be sure to remember his mother, too.
I would advise him that a being a father means he should discipline. And he should also hug. That real men know the right moment for each, and that the two actions are not always mutually exclusive.
I'd acknowledge that his mother might have read his mind when he was eight, but that it was probably a fair guess when he wanted an ice cream sundae or was sad about losing his soccer game. Mature men must communicate their feelings and needs--with mature words.
I'd warn him that being career-focused will be an asset, but being career-obsessed to the detriment of the rest of his life will just make him an ass.
I'd tell him to admit when he's wrong; compromise when he should; but not to defer to her for every decision. Being a man does not mean being controlling. It doesn't mean being PW'd either.
I would tell him, when he's grown, to call his father, not just his mother, more often. Mothers often learn to convey their needs by goading and guilting, but fathers miss their children too.
I'd suggest that it's all hunky-dory if she wants to cook and he prefers to mow the lawn, but that stereotypes only work if both partners are stereotypical. And I'd say that raising children is a tag-team sport, even if she happens to be a stay-at-home mom. I'd want him to understand that being tired at 8:30 p.m. is no excuse for skipping his child's bedtime story.
I would want him to know that if his favorite pet dies, tears won't make him less manly--only more human.
I'd tell him that he could ignore all the advice I've offered. But that if he was a man, a real man, he'd at least truly listen and nod his head that he's heard me, before he might disagree.
And then I'd listen to his argument, because I'd like to think I'm both man and woman enough to consider that I might be wrong.