Your coach will help you to make decisions about testing and competing. They will prepare you appropriately for these events.
When you test, your coach will usually be present at your test session to help you warm up, and to provide support and/or guidance as you need it. Similarly, when you compete, you should expect that the coach will go to the competition with you to guide your warmup and provide any last-minute support you need (they usually call it “putting you on the ice”).