Milan is a beautiful city with so much to see and do. Here's an ideal itinerary for 4 days in Milan:

Day 1:

• Start your day by visiting the iconic Duomo di Milano, one of the largest cathedrals in the world. You can climb to the top of the cathedral for stunning views of the city.
• After that, head to Galleria Vittorio Emanuele II, one of the world's oldest shopping malls. It's a great place to shop for luxury Italian brands or just admire the beautiful architecture.
• For lunch, try some authentic Italian pizza at Pizzeria Spontini or Luini Panzerotti.
• In the afternoon, visit the famous La Scala opera house and museum. You can take a guided tour to learn about the history of this iconic venue.
• End your day by strolling through the trendy Navigli district, known for its picturesque canals and vibrant nightlife.

Day 2:

• Start your day by visiting the Pinacoteca di Brera, one of Italy's most important art museums. It houses works by famous artists such as Raphael, Caravaggio, and Rembrandt.
• After that, head to Sforza Castle, a medieval fortress that now houses several museums and art collections.
• For lunch, try some traditional Milanese dishes like risotto alla Milanese or ossobuco at Trattoria Milanese or Ratanà.
• In the afternoon, visit the modern and contemporary art museum, Museo del Novecento, located in Piazza del Duomo.
• End your day by taking a relaxing walk through Parco Sempione, a large park located near Sforza Castle.

Day 3:

• Start your day by visiting the historic Santa Maria delle Grazie church, home to Leonardo da Vinci's famous painting, The Last Supper. Be sure to book your tickets in advance as they sell out quickly.
• After that, head to the trendy Brera district, known for its art galleries, boutiques, and cafes. It's a great place to shop for unique souvenirs or enjoy a cup of coffee.
• For lunch, try some delicious street food at Mercato Metropolitano or El Brellin.
• In the afternoon, visit the beautiful Villa Necchi Campiglio, a historic mansion with stunning gardens and art collections.
• End your day by taking a relaxing walk through the peaceful Giardini Pubblici Indro Montanelli park.

Day 4:

• Start your day by visiting the famous fashion district, Quadrilatero della Moda, where you can shop for luxury Italian brands like Prada, Gucci, and Armani.
• After that, head to the futuristic CityLife district, home to the impressive Isozaki Tower and the Allianz Tower.
• For lunch, try some delicious seafood at Langosteria or Il Luogo di Aimo e Nadia.
• In the afternoon, visit the Leonardo da Vinci Museum of Science and Technology, which houses interactive exhibits on science, technology, and engineering.
• End your day by taking a relaxing boat ride on the Navigli canals, enjoying the beautiful views of the city from the water.

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