Upcycle Chrome School Chair with Leather?

[Aching]

Hello, 

I own the above school chair (a mid-century product from a company called MELSUR). I'd love to replace the green material with leather and was hoping for some guidance as far as technique (sewing versus using grommets), the proper leather thickness, and anything else I might not have considered as a beginner. 

I've seen this upcycle done with lawn chairs but never a school chair. Thanks for your help!