For a long time, most of my "serious" works have been fan fiction. Other authors or creators offer me so much inspiration, but now I'm struggling a little when it comes to original writing. Any tips on how I can make this jump?
Use your fandoms as a starting point. I’ve got a couple characters within original works who mutated from fan characters.
What are you favorite aspects of the fandom you often write about? If you adore the characters, examine what that book/show/series/etc does well in terms of character development and design and try to apply that to your own works.
Lately I’ve found I’ve been enjoying stories that include bully characters that get character development (particularly the kind where they’re slightly less shitty but they don’t make a complete cheesy good guy transformation) and I’ve also made a character that falls into common tropes of this character archetype. Taking this trope and applying it to my own setting and story and having him interact with other characters has given me a lot to work with, and it’s been a delight.
Similarly, if you love the world building of a series, see what’s done really well and see how you can make use of those techniques. Amazing dialogue or writing style? Sit down and study all of the lines that you loved and really analyze why. Apply to your writing.
Don’t be afraid to wrangle some tropes (or things that you might consider cliches) into your own work based on ones you’ve found yourself enjoying in other works.
If your fanfictions are divergent enough from the source material, consider using them as a base for your own thing.