Get the flexy glass cut accordingly to the measurements you have on the walls around the burners.
Remove the electrical sockets from the wall (if you have one),make a hole in the flexy glass that would fit the socket area.
Place the flexy glass in place and use small screws in the corners (drill small holes in the flexy glass in advance)
Place the electrical socket back in place and on top of the flexy glass.
When I learn how to add a picture I will do so.