PlanesFollow

Ok, my bard is getting close to 46 now, and will soon be able to enter the planes. Is there a guide that someone could link me to that will give me an idea of how the planes work?

I've never seen the planes before and am guessing that it is a progression. Is this correct? Do I have to complete something in a certain plane to gain access to another?

Are level 46-50 will I just need a group or multi-groups to survive in the planes?