Sure, I'd be happy to help you plan your 4-day trip to Kodaikanal! Here's an ideal itinerary for you:

Day 1:

• Start your day with a visit to the Kodaikanal Lake, which is a beautiful man-made lake surrounded by lush greenery. You can take a boat ride or simply enjoy the scenic views.
• Next, head to the Coaker's Walk, which is a picturesque walking trail that offers stunning views of the valley below.
• After that, visit the Bryant Park, which is a botanical garden that houses a variety of flowers and plants. You can also enjoy a picnic here.
• In the evening, visit the Kurinji Andavar Temple, which is dedicated to Lord Murugan and is known for its beautiful architecture.

Day 2:

• Start your day with a visit to the Pillar Rocks, which are a set of three giant rock pillars that offer breathtaking views of the valley below.
• Next, head to the Guna Caves, which are natural caves that are believed to have been formed by a meteorite. The caves are surrounded by lush greenery and offer a unique experience.
• After that, visit the Pine Forest, which is a dense forest of pine trees that offers a serene and peaceful atmosphere.
• In the evening, visit the Bear Shola Falls, which is a beautiful waterfall surrounded by lush greenery.

Day 3:

• Start your day with a visit to the Dolphin's Nose, which is a viewpoint that offers stunning views of the valley below. You can also enjoy a trek to reach the viewpoint.
• Next, head to the Berijam Lake, which is a beautiful lake surrounded by dense forests. You can enjoy a boat ride or simply relax by the lake.
• After that, visit the Green Valley View, which is another viewpoint that offers stunning views of the valley below.
• In the evening, visit the Kodaikanal Solar Observatory, which is a research facility that offers a unique experience.

Day 4:

• Start your day with a visit to the Palani Hills Wildlife Sanctuary, which is a beautiful sanctuary that houses a variety of flora and fauna. You can enjoy a safari or simply explore the sanctuary on foot.
• Next, head to the Silver Cascade Falls, which is a beautiful waterfall surrounded by lush greenery.
• After that, visit the Shembaganur Museum of Natural History, which is a museum that houses a variety of exhibits related to natural history.
• In the evening, enjoy a leisurely stroll through the town and explore the local markets.

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