Vary your style. You need a mixture of long and short sentences and paragraphs, which can be used to help pace too.
Vary what you read - fiction, non-fiction, in your genre and outside it. Not only is it more interesting for your reading life, you’ll be influenced by good writing from a variety of sources, which is bound to help your own work. Oh and be influenced by the best!
Have a list of things to do and deadlines to meet. It keeps your writing varied and meeting deadlines regularly is what you would do once you turn professional so it is not a bad idea to get into that habit now!
Vary how you show your characters. Moments of weakness in a character can be used to strengthen their portrayal. We all have moments like this - fictional characters should reflect that. It is then what real and fictional people do after having such moments that can add or make a story.