How do I gain rank?

Im not sure if your talkin on the forums or ingame so im gonna talk about both.

In the forums you need to post to gain rank.

Ingame you need to build units, or get more workers and crystals to raise your score. Raising your score will raise your power so that will raise your ranks

If you need help in the game apply for a mentor Here

Or read our BD wiki

Be best if you actually gave him specific pages to read

Take a look at:
Scoring and Ranking - It's probably the most relevant