In this tournament fans who enter will be ranked on a global leaderboard based on who achieves the highest accumulated score. That means that every score you get for each tournament race you enter will accumulate and the player with the highest accumulated score wins.
Mostly you will be able to select the track you wish to compete on, some people will find they excel on a given track, this is up to you. You can always try and select the track of your choice by using the "Track Select Mystery Box" in the "Last Change Performance Boost Menu"
Occasionally you will see that this type of tournament is restricted to one specific track, mostly this will be the case if we are giving away tickets to a specific race, for example Phillip Island in Australia where the Australian MotoGP are going to be awarding tickets to winners. In this case you would race the Phillip Island track.
The best way of improving your odds of achieving the highest possible score is to practice getting your combo up so your score accelerates as fast as possible, and use those Last Chance Performance Boosts like "Combo Insurance" which means you don't have to start from zero if you miss a brake or acceleration marker.
Good Luck - Race to win with MotoGP.