Although not every challenges will ask you to validate the rules of the game, some still do. And this could be caused by several different reasons, ranging from the difficulty level of the rules of the challenge (so the rules section serves as a reminder for all participants and is something that you can refer back to) or simply because there is an extremely important element in the rule of the challenge that the administrator does not want you to miss.
Regardless of the reason behind it, in order to validate the rules of a certain challenge, you just have to follow these simple steps:
Get into the space of the challenge in question, by clicking on "Challenges" in the left menu and selecting the space you need to access in the list,
You will be directed to the "Rules" section of the challenge
Read the rules and check the box below it, next to the text "I confirm that I have read and accepted the rules above, which are to be adhered to while participating in this challenge."
Click on the button "Accept and Continue"
Taa-daa !
And may the odds be ever in your favor!