re: As a manager, how do you manage people way older than you?

Look at it like a team.
Each person brings a specific skill.
You praise them for good things and suggest ways to do this differently if they do things poorly.
Make them come up with a way to do things better.
If they been in a position for awhile that why I said the above.

You always have some you have to look over their backs and others you can give a list of task, they will get it done.

It does not matter any age always knows each persons strength and weaknesses. Use this to make everyone gel as a team.