Unless you play a small map don't focus too early on your target.
Be careful to protect players that are not your target. If you see someone having huge bonus, even if he isn't your target you may want to break his bonus.
Often people focus too much on their target while someone else win the game.
Also don't use all your forces against your target especially early in the game. ( unless you have reasonable chance to make the kill ofc).
If you use all your force you may then become an easy target for your assassin.
Don't trust PM's from other players telling you that attacking major political figures will win you the game. I spent too many long months trying to destabilise the government of Papua New Guinea to fall for that one again.
the world is in greater peril from those who tolerate or encourage evil than from those who actually commit it- Albert Einstein