In reply to kipper12:
I made one just last week for a friend's Beauceron when they're out herding sheep in strong sunlight: dog gets hot when taking his tea break.
Piece of silvery tarp (cut from a Decathlon sun shelter found abandoned in the woods), eight eyelets set into two sides of the rectangle. She puts it up like an A frame tent using walking poles; like a slab sided shelter or with one pole like a lopsided teepee - depends on terrain - pegs/guides and dog happy until sheep start playing up again.
I imagine one can buy similar material online; the metal gizmo for setting the eyelets was £15 from a DIY centre; pegs and cord for guys could be sourced at Decathlon.
Had I not found that ruined tent in the forest, and if I didn't like making things, I'd probably suggested that she buy one of those pop-up tents from Decathlon. Unsightly disc to carry around, but light weight; and unless very high wind, no need for pegs cos dog weighs close to 50kg and would hold it down in all but strongest wind.
Happy Easter