how to sell things and make money online starts with identifying what people are already searching for, then supplying that demand. Use research tools to discover profitable niches, source or create products, and choose platforms like Amazon, Etsy, or your own Shopify store. The key to profit lies in strong product listings, appealing images, and optimized keywords. Fulfillment can be handled through third parties or platforms like FBA. Advertising, influencer marketing, and social proof from reviews all increase conversion rates. By tracking margins and reinvesting wisely, sellers can scale up their operations and build sustainable income streams.