How can I become a Dedicated Fan, Die-Hard fã or Fanatic of a club?

This has been asked many times.

Just do what you normally do: get on the club often and enviar things to it.
Sooner or later, you'll get a medal.
There isn't any specific way, that's the F4's secret.

Just continue to do what you normally do, and you'll have one in no time ^^