1 big white t-shirt
2 m of lace
1/2 m of ribbon
2 sheets of cardboard (A4)
Step 1: The Wings
Bend the cardboard diagonally and cut the extra piece so that you get a double triangle.
Insert the cardboard into the sleeve and sew it using the sewing machine so that it doesn't move.
Step 2: The New Sleeves
Cut with scissors and make a simple hem, or use lace to do it.
Also sew lace around the collar of the shirt.
Step 3: The Back
Tie them together so that the wings lift up.
Step 4: The End
Guaranteed effect ;)