Writing is no different. So...that...just...then...walk...look...was...just a few of the words that continually show up in first drafts. That's where revising comes in handy. Most of these words can be deleted on the spot. Sometimes it fits and should be left alone. Sometimes tweaking is necessary: rephrasing, rearranging, or plain old cutting. But be careful when turning to a thesaurus for help. Replacing "look" with "gaze" over and over just creates a new monster. Plus, the mood you're trying to convey can change the instant you replace "walk" with "strut" or "stomp" or "slink".
Repetition isn't limited to a single word. Phrases and actions and ways we show emotion tend to pop up over and over. It's one thing when a character has a unique trait or a certain way of expressing herself, but if every single time my main character shows her fear through a "racing pulse" or "rapid heartbeat," readers' eyes start to roll.
When revision fails to pick up all the redundancy, that's where critique groups and beta readers swoop in and save the day. It took one of my beta readers to point out my overuse of "beating hearts". I dumped the "pounding chest" and unfortunately picked up a new bad habit, the "twisted tummy". Thankfully, not within the same manuscript.
No matter how many other eyes review your work, overused words, cliches and actions will slip through. Putting a draft aside for a good chunk of time is essential. Then you can take a fresh look and catch anything that drowns your story in repetition.
So, just know you're, like, not alone. Look over your work, get feedback, then set it aside for refreshed eyes. That's the key to ending redundancy.