Are you an art historian/humanities scholar who wants to do more public engagement? Here's a thread with some of my thoughts/advice. Please add more!
Make it easy to contact you and figure what you know. Think of an editor looking for someone to write a piece or a community member looking for someone to help them figure out an issue. They need to know what you can be a resource about.
So make that clear in your social media bios. And have some form of online presence, like a personal website that can let you show some personality and tell people about yourself in non-academic language. It can (and probably should!) be super simple.
Then, figure out what idea you want to get across to people. Is there something about your field you think is incredibly obvious or fascinating but are always surprised not more people know about? Perfect! You've got your topic.
Now, pick a format. I love how creative you can get with public engagement. Podcasts, visual art, standup, teaching open classes, tours, community talks, working with journalists, advising politicians, serious social media posts, funny social media posts... so many options!
BTW, the science educators have got the humanities people beat. Follow some of them for ideas!
For an overview of some of the more traditional forms of writing for the public, I recommend https://www.amazon.com/Going-Public-Scientists-Chicago-Publishing/dp/022636478X - it's got discussions of practical aspects of pitching and writing, and also talks about planning for potential downsides, like trolling.
Once you set your sights on a form, get some advice about it. Nobody's born knowing how to write an op-ed, for example... that's why there's the OpEd Project: https://www.theopedproject.org/oped-basics
Some people can study examples of the type of thing they want to do and then figure out how to do it. My brain doesn't work that way, so I've taken many classes and read lots of websites on "how to do incredibly specific thing," like pitch a long-form article.
Fortunatly, there's so many people who've been willing to write said "how to do incredibly specific thing" websites. If you want to know how I learned to do a type of thing I've done, ask and I'll give recommendations.
Now it's time to execute. If you're a genius, you'll put your idea into the form you've chosen and everyone will bow before you. If are an actual human, you'll need feedback. I've created first drafts in classes or with a writing coach, and...
...endlessly pestered friends for feedback, and also managed to get editors who were willing to work with me on not-fully-baked ideas. If I were smarter, I'd have found other grad students or ECRs to do a mutual support group - I'll read your pitch if you'll read mine, etc.
And then it's time to submit! This varies so much that it's hard to give general advice, but, build your network. Follow editors on social media. Start a list of venues you'd like to see your work in. Investigate the options in your community for performing/writing/etc.