Oh, there are many! Here are the top three according to me:
Make a habit of testing your code properly from the very beginning. It doesn't matter how good you are at a particular technology. Care for the edge cases. Learn some testing techniques.
Don't love your stack! Don't be someone who says "JavaScript is bad" or "NodeJS can't scale." Keep an attitude to learn something new every day.
Manage distractions! Find out how to prioritize things and manage your time properly.