So in August there's an annual flash picnic called Soiree en Blanc.
It's a big fancy picnic, where everyone wears white.
You bring your food, but emphasis on fancy, ie real china, table clothes. Some people go all out and have brought white couches and sectionals. I've gone to about three of them.
The Attention Horse headdress will be worn.
Anyways I'm looking at white jumpsuits to wear. I've found these on Etsy

https://www.etsy.com/listing/2.....er_profile

https://www.etsy.com/listing/5.....er_profile

https://www.etsy.com/listing/2.....ile&e

will have bra issues
https://www.etsy.com/listing/5.....3&

much more casual

https://www.etsy.com/listing/2.....er_profile