Think of your own tactic, figure your opponent's tactic, gain 1000 points as first - win the game.
Tichu is a game in which neither two strifes are the same. Seems simple right? It actually isn't because in this game you can never think that victory is yours. The goal is simple, to gain as many points as it's feasible which is done by getting rid of the cards from your hand as soon as possible. It is a team-based game that is a mix between Poker (Various card sequences) and Bridge (2vs2).
They say that Tichu is a game of which 'rules cannot be explained'.