Glue for printed vinyl banner
Im supposing you'll leave it there... 
You'll need a strong 

glue that is resistant to the most dramatic climates in the world (i know it from experience).
This glue does not affect the banner at all. One thing though,  do not put too much glue! "dot, dot, not a lot", this glue expands 3 times what you put! so be careful! This glue can be used for everything.