Hi Eileen, here is one I made last year, turned out great.
Eileen, if you click on "explore projects" and type in "terrarium" in the search box and hit enter, there are quite a number of terrarium ideas. I have chosen one for you but there are quite a number more you might like better! https://www.hometalk.com/7421609/diy-terrarium
Here's a helpful video: https://www.youtube.com/watch?v=3y_e1dzL61Y
This video should help. https://www.youtube.com/watch?v=3y_e1dzL61Y