You can create tournaments by choosing the Tournaments option from the top left Menu. In here select create a new team using the + button.
Then you can enter the Tournament name, Tournament logo, Location of the tournament and start and end dates of the tournament. Once the tournament has been set up, you can start adding existing teams into the Tournament to create a list of teams. From the list of Teams within the Tournament, you can organize the Matches and Groups that make up your Tournament.