How can I print my photos at a kiosk?

I have an iPhone 6+ with a mere 16GB storage I enabled iCloud photo library so as to store my photos in the cloud and open up some space. I would like to print some of my photos at a kiosk but the app can't get the pictures from my phone as the "full resolution" photos are now stored in the cloud. Is there a work around for this?

First of all, unless you're planning on printing poster size photos, the optimized photos stored on your device should be more than sufficient.

Secondly, the kiosk should have a way for you to print your photos. I'd like to also think that there is an assistant at the kiosk to provide help, if necessary.