Broad-brimmed straw hats are the best as they are light, breathable, and all-natural. Try to procure one made anywhere but a sweatshop.
I wear a polyester "Tilley hat" sometimes, but it looks like an outdoorsman's hat. They make a hemp version in British tan which is wonderful. Not straw, though. It's a cloth hat. Those can be nice.
A big floppy straw hat rightly trimmed looks absolutely fetching on a lady with the right summery outfit to match! You'll find something out there that fits your style and budget, of course.
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Your neurodiverse (Aspie) score: 134 of 200
Your neurotypical (non-autistic) score: 72 of 200
You are very likely neurodiverse (Aspie)