Basket full of parasols will be a shady idea to help your guests stay cool. They come in a variety of colors to match with anything you are thinking. Guests can them keep them after as a gift. Maybe add a tag letting them know. “A Gift to you to shade yourself on our special day. Please keep as a gift from us”.
This shows a large wicker basket but there are many other ways to display as well. Use your imagination. It could even be something that you already own. Or something borrowed:)
You can also supply a beach mat for them to take off their shoes next to the basket.
