Build a fort, not just your ordinary blankets on the sofa kind. Go crazy and find every single cushion you own, duvet, blanket, vintage scarves, we are talking all the trimmings. Gently climb inside and watch your favourite TV show (cough, game of thrones.)
Pick up a book lay down for a few hours and just read turning off everything else happening around you, falling into the story. Recently i've started Donna Tartt's "The Goldfinch" it's exquisite.
Make the most of your time.
Knitting a patchwork blanket? Complete as many squares as you can manage, the feeling of accomplishment afterwards will be extremely rewarding.
Start a new TV Series.
Nap. Once, twice, hell three times. Snuggle up to a pet, boyfriend or loved one and take five minutes away from the world.