Either don't post it ... Or accept that it will be stolen.
Those are the only two choices, as far as putting creative works on the internet. Even sites that require membership, I've seen works stolen and put on other sites.
I've decided to start a writing blog where I hope to document my journey as a writer and share tips with other people. I'd like to post some of my work so that I can get reviews, but I'm worried that people might steal my ideas. What should I do?
I taught a creative writing class for a few years and set up a web site where my students could publish their work and share it with the world. Almost without exception they refused to post it because "somebody might steal it".
And so they might, but it's not much fun writing if you don't have an audience.
A young man once approached Isaac Asimov and said, "I have a great idea for a story. I'll give it to you, you write the story, and we'll split the profits." Asimov replied, "I've got a better thought. I'll give you an idea, you write the story and we'll share the proceeds."
Taylor, for creative people ideas are everywhere. You can keep yours to yourself or you can share them with the world. It's up to you but it's more rewarding to share. If you owned a Ferrari you wouldn't keep it locked in your garage in case somebody scratched it. So it is with writing.
But it's a wonderful recreation and will impact on the whole of your life. Good luck, whichever way you decide to go.