Learn how to properly sound mix and understand different audio filters.
Look up what Highpass filters are, how to change audio frequencies, or what a compressor does.
You’ll become so valuable if you can do a good temp sound mix.
Not only that, if you can create good temp VFX too, you’ll be sought after. Know how to motion track, create titles/graphics, split screens, etc.
Learn all of these skills because the closer you can make the edit feel finished, the better.