Stealth tips for MGS Delta

Playing this as my first game in the series and I kind of feel I'm selling myself short on it. The game is giving me a lot of tools, but everything I do other than using the tranquilizer gun ends up with me getting caught and in a big firefight. Do I just need to be more patient? Or maybe make more of an effort to get through areas without taking down guards? Some sections feel impossible to clear without shooting, like showing up on the docks of that warehouse. I just started my fight with The Fear.