Cheapest Keys Organizer (Flexible to Add and Remove)

I really like those ideas of making keys into swiss army knife style, but i felt that there is lots of constraints in size, fix numbers of keys and too time consuming to make one.

So I thought of a simplest way to organize ur keys where u can have the flexibility of changing them as and when u had to. This way is much more cost effective and less time consuming.

Share with me ur version if u had made one. :)