How the best submissions are chosen?

I can’t find how to choose a submission.
Is it done automatically for us and if so how? Using the best test score?

Hello Tatiana,

A form will be made available the day before the challenge concludes, and the deadline for submission will be set for 12 hours after the challenge ends. Please check your email for the form link, which will also be shared on the leaderboard.

All the best!