How do you win a challenge in Uno and what strategies can help you come out victorious?

To win a challenge in Uno, you must be the first player to get rid of all your cards. Strategies that can help you win include saving powerful cards for the right moment, paying attention to your opponents' moves, and using action cards strategically to disrupt their gameplay. Additionally, keeping track of the cards that have been played can give you an advantage in planning your next moves.