The two walls will make up half your fort already, so that you can use fewer supplies. Make sure there is a couch or bookshelves around to act as support, and hang a large blanket as high as possible.
Another option you have is a clothesline blanket fort. Hang a clothesline high up across the room and dangle several blankets from it. Use clips to attach them in place if needed.
Bring pillows, stuffed animals, and other toys to make the experience as comfortable and exciting as possible!
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