To create a listing, start by choosing the appropriate platform (e.g., Etsy for crafts, eBay for goods, Airbnb for rentals). You'll typically need to register an account first. Then, look for a "Sell," "List an Item," or "Create New Listing" button. You'll be prompted to provide essential details such as a catchy title, a detailed description, high-quality photos, pricing, and category selection. Be sure to highlight unique features and set clear terms, like shipping costs or availability, to attract potential buyers or guests.