Ohio State and Auburn Universities and the National Collegiate Athletic Association: This is how it's done. Create any code you like. Make it strict, make it lax, make it ordinary, make it weird. Make them read it, make them sign it, paint it on the wall or whatever else you think needs doing. But when someone crosses whatever line you've drawn, follow through with it.
No, "We'll suspend them at the start of next season, after the bowl game." No, "Well, his dad was shopping him around to different schools but he didn't know anything about it." No lame excuses, no ethical and logical contortions that would make Plastic Man wince, just because a bowl win or a national title may be on the line.
Lord knows, according to a couple of different books out these days, not many colleges teach kids all that much anyway. It'd be nice if somebody thought about teaching them what it means to be an adult and accept the consequences of your own actions.