Here's how I did it: I bought four sheets at an estate sale. (Yes, they are used sheets, and if that grosses you out then I'm sorry. I did wash them! If I had to buy new sheets I couldn't have afforded to make it.) I sewed 2 sheets together lengthwise. I drew horizontal lines every nine inches with a disappearing ink pen. Then I just gathered the fabric as I sewed. When I had all the gathering complete (And I wanted to rip out all my hair at this point) I sewed over the gathered seams with some bias tape that I found at a yard sale several months back. Then I cut the remaining sheet to fit the size of the duvet that I had and sewed the gathered cover to this sheet right sides together, leaving an opening to turn it right side out and slide in the duvet cover. I finished by sewing 2 pillow shams with the same gathering technique and then 2 throw pillows with some lace that I also found at a garage sale.
Super easy! And I am not the only one who is enjoying my big, fluffy, new cloud.
Cost: 4 used sheets: $2.50
2 spools of thread: $3 (I used a lot of thread for this project!)
Bias Tape: $0.25
Lace: $0.25
Total Cost of duvet cover and 4 pillows: $6.00