How to make something "mountable"

Hello! I'm going to make a much smaller version of this as a shelf for under my TV. I'm hoping to make it something that I can mount on the wall. Is there anything special that has to be done so it's safe to hangup?

https://preview.redd.it/nr67grijhp8e1.jpg?width=1290&format=pjpg&auto=webp&s=963d9fd7682ed1d1eef234b145495d24e4155259