To book a multi-destination flight on Southwest, visit Southwest.com and choose the “Advanced Search” or “Multi-city” tab. Enter your desired cities and dates for each leg of your journey. The site will display flight options for each segment, allowing you to select the best combination. Southwest’s no-change-fee policy also makes it easy to adjust any leg of your trip if plans change. If you prefer personal assistance, you can call Southwest’s customer service, and they’ll help you structure your itinerary step by step.