Close your eyes and listen to the sounds of forest. The sound of wind and grass calms your mind.

Since nature is not static, constant noise can be a great help in calming the mind. In particular, research has shown that the sounds of the forest generate theta waves, which help with sleep, and SMR waves, which help improve thinking skills.
The sounds of the forest greatly increase happiness in life and relieve stress and tension.
These days, we need rest more than ever. Listen to the sounds of nature.