How do I become a Lieutenant grade 4 in halo 3?

[coo c]

Yea i know i need experience to level up but i don't want to skip lieutenant grade 4 and go to captain because i don't want to be a captain so if you could help me that be great

 

[Jordan M]

play ranked games..nvr social

 

[Shikamaru]

Play a ton of unranked games after you reach Lieutenant grade 1. Just get a skill level up to 10, then play only unranked or stop playing a game if you're about to hit 20. You can't hit 20 or else you'll shoot up to Captain.