I recently went to Japan to study where Shinrin-Yoku started. We took a long bus ride out to the Japanese Alps to meet with old Japanese communities and health care providers to learn more about the latest research on why engaging your senses in nature is so healing: physically, emotionally and spiritually.
I would like to share two term that I learned with you. The first term is Komorebi which translates to a beautiful practice that involves focusing on shadows as they move, which happens to be very relaxing over time. Try wandering out into the forest and find shadow play (maybe leaves from trees as the sun filters though) and keep a steady gaze for 10 minutes. You will be slowly transformed into a deeply relaxed state. You can even bring along a white piece of paper to catch your shadows- I have enjoyed deepening this experience by sketching these shadows with charcoal and then adding some water color for a more dramatic effect.
The second term that I learned is called Yuragi- which is a combination of nature sounds that leave you feeling relaxed. Yuragi can be personalized just for you taste. I found an app called Yuragi Plus that allows you to combine various nature sounds that you enjoy. You can also record your own sounds on the app. LOVE this app. https://yuragiplus.com/?lang=en-US