Crew Ranks
There's 3 different crew ranks currently, so it's understandable that this might seem confusing to some of you guys. I'll try to explain these:

1. In-game Crew Rank
This rank determines what kind of crew stuff you can buy. Like crew emblem, colour, masks and smoke. You increase your crew-rank exactly the same way as you increase your normal rank: By earning RP. Just remember that you need to have the crew as active. The crew rank title changes when you progress, starting out as a baby llama (crew rank 1-10) to maybe one day maybe earning Dalai Llama status (crew rank >90). One way to see this rank: start -> online -> players -> yourself and then the number in the corner of the crew emblem.

2. The Hierarchy Rank
To rank up in the hierarchy you've to be involved in the crew. It's not hard to rank up, and if you act according to crew policy you can basically move from muscle to commissioner within 30 days. Especially p. 13 is very effective for ranking up in the hierarchy, so make sure to check this out -> http://spittingllamas.createaforum.com/gta-online/the-perfect-llama/

3. Forum Rank
Perhaps the least important rank, but is based on your contribution to the forum in terms of posts. 0-9 posts = baby llama, 10+ spitting llama etc. If you're organising events and want to help out additionally, you can become a moderator on a specific board, or even global moderator (all boards).