Trusted is not applied for. Moderator is the only position you apply for.
Earn trusted by essentially being nice to people and not causing trouble on the server. Be patient and don't ask for it. An Operator wi promote you when they feel like you have earned it. Well, admin too. Either way, kissing up will not work so don't try that, it will just make it look obvious that's you're desperate for Trsuted.
Hopefully that helped answer any questions you have about trusted.
Oh, and don't apply for mod until you have gotten trusted.
Read my below post. Sorry, had assumed you were applying for trusted by reading the title