Tips & strategy
Keep track of which numbers have run dry. Once all the tiles showing a particular number are down, no more can ever be played on an end showing that number. If you can leave both open ends showing an exhausted number, your opponent is forced to draw or pass while you keep playing.
Get rid of your heavy tiles early, especially high doubles. If the game locks with tiles still in hand, the player holding the fewest pips wins, so a five-six left in your hand at the end is eleven points working against you. Play the expensive tiles while you still have a choice.
Watch when your opponent draws. Every draw tells you they had nothing to match the open ends, which reveals numbers they are missing. Aim your following plays to keep those same numbers exposed, and you can force draw after draw.
Hold a tile that matches a number you play often, so you always have an answer. Dumping all your copies of one number early can leave you unable to respond when the chain swings back to it, forcing you to draw at the worst moment.