Start by giving them descriptive filenames (like blue-running-shoes.jpg) and writing clear, keyword-rich alt text. Compress images using tools like TinyPNG to improve load speed, and use relevant captions where appropriate. Keep images close to matching text for better context, and use WebP or JPEG formats for the best balance of quality and size. Add structured data if applicable (like product or recipe markup), and include your images in an image sitemap to help Google index them. Make sure your site is mobile-friendly and displays images responsively. Lastly, always use original visuals—Google prefers unique content over generic stock photos.