Free: Contests & Raffles.
I would use long shockcorded tent poles. Two or three, make pvc pockets for the pole ends.Bend them dome like over the raft. Where they cross on top tape with gorilla tape.Use lite weight cover. Tale down when moving.I do this over my utility trailer for covered storage I. Hunting camp.
Since it’s already blue, have you considered adding red, yellow, and white to turn it into a giant loaf of wonder bread?