Hello everyone, I am posting on this community to solicit advice on avoiding heat stroke while not looking like a fool. Currently I own several 95% polyester 5% spandex short-sleeve button-ups as well as one 100% linen long-sleeve button-up. I find both to be quite suitable for hot weather, but would love suggestions that aren't T-shirts and button-ups. Additionally, what options are there for summer pants? And what actually looks good with shorts? When I wear them I look like a camp councilor - or worse, a kid attending summer camp. 
Feel free to discuss dresses and skirts as well, although I am personally not interested. Oh yes, and I suppose summer hats could be useful too. Thank you in advance.
Linen is the best fabric for hot weather. It holds a great deal more water by weight that cotton, meaning you can sweat a lot more before the material becomes saturated and can't pull more sweat away from your skin. It wicks moisture and breathes much better than cotton, meaning it pulls water in and allows water to evaporate much faster. The result is that you stay cool and dry. It's not as soft as cotton but I find the texture more pleasant, and at any rate if you don't have any issues with it then you'll get used to the differing texture in a day or two.
This effect of linen works well if it is flowy, cuts that are very cloth to your skin mean there is not enough air moving around, this is why some tight linen suits don't feel as nice as the comfy flowy alternatives in high heat.
Also many linen suits are lined, sometimes even with poly, which makes them worse than useless compared to a light wool/silk lined suit