Firstly you have to atleast be in fc for around 6 months + [My opinion]
Secondly you need to be really helpful to the fc, here are examples : Donate to Drops, Promote Our Fc and Do giveaways.
Third, You need to be trusted in the fc.
Fourthly/fourth? [IDEK ] You Need to be a good member of fc, have a nice personality and be friendly and known by people in fc
Be in the Fc's Good books.
Iam not saying this because I got a rank and I am not bragging or anything I don't want people thinking that
This is just what I think =D
List down anything else you guys would give as Advice =D