Which design pattern should I use for console rasing sim?

I need to make a console racing simulator using gof (or other) design patterns, but I don't know which one to use here.

I already made the game, but it's more like "OOP for the sake of OOP style". It has a Car class which contains drive, control and gameover methods and and Obstacle method, which generates and moves an obstacles.

Which design pattern should I use to make the game? Can I recomposit existing classes or must I start it all from scratch?

Thank you for any help.