Advice Planning a 6-Day Barcelona Trip - Need Advice!

Tour season is fast approaching, and I'm finalizing plans for a 6-day trip to Barcelona. I've heard so much about the city's architecture, beaches, and vibrant culture, but I'm a bit overwhelmed with all the options. I want to make sure I don't miss the must-see spots like Sagrada Familia and Park Güell, but I also want to explore some hidden gems. Does anyone have a recommended itinerary or tips for making the most out of 6 days in Barcelona? Also, any advice on local dining spots or day trips would be greatly appreciated!