Baby, It's Cold Outside
As long as you've got that blanket handy from yesterday, you might as well put it to good use today on Wear a Blanket Day by wearing it to keep warm.
If you happened to actually wear it for a while yesterday, that's okay.
If I were you, I wouldn't pull a blanket off my bed for wearing purposes. You probably have another smaller one lying around that you can wear.
You can get fancy and create something out of your blanket like a cape or a cowl or something similar from Star Wars.
Technically, just covering up with a blanket (on the couch or wherever) is a fair way to celebrate today.
Technically, too, covering yourself with a tiny piece of cloth, say, a baby blanket or doll blanket, would qualify for this special day.
Enjoy your blanket.