Here's an ideal itinerary for 6 days in Izmir:

Day 1: Arrival and City Tour

• Arrive in Izmir and check into your hotel
• Start your day with a traditional Turkish breakfast at a local cafe
• Visit the Konak Square and see the iconic clock tower
• Explore the Kemeralti Bazaar, one of the oldest and largest markets in Turkey
• Visit the Izmir Archaeological Museum to learn about the city's rich history
• End your day with a sunset walk along the Kordon, a beautiful waterfront promenade

Day 2: Ephesus and Sirince Village

• Take a day trip to the ancient city of Ephesus, one of the best-preserved Roman cities in the world
• Visit the Temple of Artemis, one of the Seven Wonders of the Ancient World
• Explore the charming village of Sirince, known for its wine and olive oil production
• Enjoy a traditional Turkish lunch at a local restaurant

Day 3: Cesme and Alacati

• Take a day trip to the picturesque town of Cesme, known for its beautiful beaches and thermal springs
• Visit the Cesme Castle and the Ottoman caravanserai
• Explore the charming town of Alacati, known for its narrow streets and traditional stone houses
• Enjoy a relaxing afternoon at one of the town's many cafes or restaurants

Day 4: Izmir Bay and Karaburun Peninsula

• Take a boat tour of the Izmir Bay, one of the most beautiful bays in Turkey
• Visit the Karaburun Peninsula, known for its stunning natural beauty and crystal-clear waters
• Enjoy a swim in the Aegean Sea and a picnic lunch on the beach

Day 5: Bergama and Asclepion

• Take a day trip to the ancient city of Bergama, known for its impressive ruins and historical significance
• Visit the Asclepion, an ancient healing center dedicated to the god of medicine
• Explore the Acropolis of Pergamon, one of the most important archaeological sites in Turkey
• Enjoy a traditional Turkish dinner at a local restaurant

Day 6: Izmir and Departure

• Spend your last day in Izmir exploring the city at your own pace
• Visit the Izmir Wildlife Park, a great place to see local wildlife and enjoy nature
• Enjoy a final Turkish meal at a local restaurant before departing for the airport

I hope this itinerary helps you plan your trip to Izmir!