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

Other days

one

One Day
lumpy rug

Lumpy Rug Day
stud

Stud Day
artists

Artists Day
bow tie

Bow Tie Day
cuddle up

Cuddle Up Day
brow

Brow Day
nail polish

Nail Polish Day
ruby

Ruby Day
hoodie

Hoodie Day