A trial period is 2-3 weeks can be more ofc.. depending.
To reach the rank member / raider You must be active on all raids.. show good skill to your class, have consumables on each raid, giving 210% of yourself and your class.. Working on your gear all the time. the right sockets in your gear. help out the guild / guildees.
Have good behaviour. listen to your raidleader, Do what your are told. and Have / be on vent is a MUST!