Our church worships at a school, so we can’t put up any banners permanently.  However, we want to raise visibility while we are there so people can easily find us.  We put up banners on the chain link fence

Zip ties work great if banners up permanently.  However, We have to ours up and down each week.  We found that these D-Ring Carabiner Hooks from Walmart (they cost 99cents for a pair) work great for this!  We found ours back by hardware / automotive section.

You can buy similar ones on Amazon: