Shower curtains. They're not just for showers anymore. Drape them over. Tuck them in. BOOM. Cushion covers. They dry fast, they can be very inexpensive, easily changed, easily cleaned.
The chair on the left is mine. See me sitting there? I'm waving... Hey!
My mom bought these at a yard sale years ago, and years after that she was selling them in her own yard sale. When I got hot and tired I had a seat in one, and that was it. Their yard sale days were over. They've been home on my porch ever since.
After some sanding and painting and shower curtains later... We read, write, and relax on the porch, mainly in these two.
Summertime and the living is easy...