Here's one idea from another Hometalk member. Wishing you the best!
The easiest way to install an outdoor curtain is with a tension rod placed inside the supports of a screened porch or pergola wall. Curtain rods made for outdoor use can also be installed on a wall, ceiling or inside mount. Choose fabric that is fade- and mildew-resistant, and manufactured for outdoor use.
What do you have to work with? Is this a porch? Pergola? A curtain rod with a shower curtain, length of pretty fabric are easy to hang with curtain clips. If lightweight, you can use a tension rod. If heavier, you will need a stronger pole that won't bend with the weight. Painters drop cloths are easy to use too and you can custom embellish them as you desire.
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