I have just discovered the beauty of making terrariums again after 30 years. I remember when you gave them as presents to everyone for everything. Of course I am starting off with the small ones and the soaked sheet floral moss. For beginners this is a good way to try different glass containers.
Pack potting soil tightly against glass and lay in the mosses and lightly tap to pack. I spray with water lightly about every two weeks.
Chair pic is from a live moss ordering company.