microservice communication: sync or async?

hey everyone, im starting to break down a monolith into microservices and im wrestling with the communication patterns. i'm seeing a lot of examples using synchronous REST calls between services, but i'm also aware of async patterns with message queues. what are your go-to strategies for deciding when to use sync vs. async communication between microservices? are there specific scenarios where one is clearly better than the other for a beginner?