"It's your turn to ___" means "You should do ___ next because you're the next in order."
You can use this phrase to say who need to do a job next, like sweeping the floor at home or hosting a meeting for your club:
It's Jamie's turn to host.
You can also use "It's ___'s turn" for things that people want to do. For example, a child who wants to play a video game might say this to her parents:
It was my turn to play next, but he stole it from me!