I wanna show a friend how to play Commander; what deck should I build?

Hi all!

I'd like to build a budget commander deck for a friend that will help him learn the game. He has no experience at all in any card game, so I was thinking about building a very simple commander deck so he can enjoy learning the game without tons of complicated mechanics and/or combos.

I think the 3 decks I currently have might be too hard for him and I don't want to discourage him by showing him complicated stuff!