Just keep playing and you will sooner or later start getting the hang of the game. Every game mode has its tactic, like in TOSOK where aim and covering yourself is crucial, while in CTF it's that plus using pickups smartly, running in certain ways or paths when you know whatis happening in one side of the map to get the flag easily, etc. All this is learned by time and experince.
Don't hack if you get frustrated sometimes, you will lose the purpose of the game and you will get caught.
Don't hack if you get frustrated sometimes, you will lose the purpose of the game and you will get caught.