It's important to be careful with what you tell your boss because even the slightest slip-up can make or break your career. One should not give unsolicited advice, inform karrierebibel.de.
Let other people finish talking in conversations – this is especially challenging if you feel offended by the statements or have a different opinion. Rejecting tasks for no reason is often bad. It is better to ask for assistance in prioritizing tasks, then the supervisor can decide which task to prioritize.