Oops, it doesn't look like 'maymays day' is a national day..

Other days

ormille

Ormille Day
eat what you want

Eat What You Want Day
china

China Day
gum

Gum Day
blanket fort

Blanket Fort Day
pampering

Pampering Day
singles

Singles Day
bow tie

Bow Tie Day
book

Book Day
get funky

Get Funky Day