You can enter the tournament when it starts by tapping the Grand Tunament button at the bottom of the map screen. It can also be entered from the Tournament Coliseum between levels 60 and 61. Participation in the tournaments requires connection with Facebook, so you will need to connect the game to Facebook first to participate.

Tournament levels work in the same way as the regular levels on the map; you need lives to be able to enter the levels, and if a level is failed, a life will be deducted from your inventory.