What are the most important dos and don'ts of academic writing?

I am trying to improve my academic writing skills and would like some clear guidance on what to follow and what to avoid. Academic writing often requires a formal tone, strong structure, and proper referencing, but many students still struggle with common mistakes. In your experience, what are the key *dos and don'ts of academic writing* that every student should know? For example, how important is clarity over complex vocabulary, and what are the biggest errors that reduce marks in assignments or research papers?