Lets say you have something like our current Power 5 conferences and G5 conferences. You pair each top-tier conference with a lower tier conference. Then, at the end of the season, the top one or two teams from the lower tier conference have a chance to move up to the top tier conference for the next season, and the bottom one or two teams from the upper tier conference have a chance to move down. You can make it an automatic swap, but the best way is to have the teams play each other for the right to be in the top conference. The worst team in the top conference plays the best team in the bottom conference. Winner is in the top conference next year, and the loser is in the bottom conference.

They do this in UK soccer. It is ridiculously fun. It means that even if your team is doing bad, your fans and players still have a reason to try to turn the season around, so they can stay in the league. And if your season is really bad, it means you have a really important post-season. Whereas for the lower tier teams, it gives them something to aim for, and these magical seasons where Nowheresville U suddenly is playing in big name schools for a season, fighting to stay alive, which makes for great story lines.

It's also a cash cow. Basically, if college football doesn't adopt relegation, capitalism is a lie.