International Rummikub is a very interesting game that is highly entertaining and attractive as it does not just rely on luck. You need to develop a tighter strategy than in regular Rummikub games, which is crucial in you winning the game.
One really important part of International Rummikub strategy is changing the hand in the event that it does not materialize or if a meld or a discard will give you information that you cannot make a set or sequence. For instance, if you are looking for a minor hand and just have tiles of low numbers a switch towards Piccolo 31 might be necessary in the event that you have a chance to hold high tiles. You need to become familiar with different patterns and learn how to associate related patterns in order to be a truly flexible and winning player in this variation of Rummikub.
Every player that knows International Rummikub strategy will tell you that if you are going for some hands you might find it quite hard to switch towards an open game. In the event that a tile that is planned in a Seven Pairs will end up in a discard pile you will see that it is hard to create any initial meld that can make the switch towards Open game.
Look at all players in the game and see what they are doing. If one keeps picking up tiles from the player that acts before him he will probably be close to a win. In such a case you will want to meld so that you do not lose big, unless you know that the player is looking for speculation. It is equally important to discard cards that will not help the player acting after you.
It is also recommended to quickly form your winning hand in the event that melds are already placed on the table and you are really close to winning. You might even draw discards or blind draws in order to obtain a Foot and win fast. Always remember that by each turn that passes players are closer to winning. This basically means that your loss chances are also growing. Players that use good International Rummikub strategy will adapt to the game and will try to meld fast if the game has been going on for a long time.