Randomly think of a thing. Let it bump around your head a bit. If the bumping gets too loud, start writing the words with the nearest writing device. See how far you get. The more words usually mean a higher degree of personal interest. Stop when it suits you.
Wait for time to pass and see if the bumping sound returns. Reread what you’ve written so far and find if it inspires you. Yes? Write as much as you can. No? Stop writing and wait for more bumping.
Repeat until it starts to feel done in your head. If it’s handwritten, type it into a computing device. When you are close to done, print it out on paper. Sit somewhere else with your favorite pen and edit your work harshly. If this piece is important, let someone else edit harshly.
Transfer all of your edits into your piece. Enter your writing into your favorite publishing platform. Proof your final piece once more. Use Grammarly because the Internet is a cruel copy editor. Hit publish and tell yourself you don’t need validation. Wait for validation and once more wait until you randomly think of a thing.