In J.K. Rowling's popular "Harry Potter" book series, Hogwarts School of Witchcraft and Wizardry is a school in which young people learn to use magic. There are many professors who teach at the school, but three of them can be considered main characters: Albus Dumbledore, Minerva McGonagall and Severus Snape. Each character has a distinct look that can be replicated in costume, mostly with purchased items needing little modification.
Begin with a long, flowing robe made of velvet or similar material. Dumbledore wore many colours in the book, while the films seemed to favour purple and wine.
Cut stars and moons out of a shimmery, gauzy fabric that slightly contrasts with the robe.
Sew or glue (with fabric glue) the stars and moons to the robe.
Make a floppy, pointed hat by first measuring the diameter of your head, then dividing that number in half. Cut two long triangles out of a fabric that matches the robe. The bases of the triangles should match the number you determined. Put the two triangles on top of each other, right side in, and sew the long sides to create a hat. Turn it right side out and put it on.
Put on a pair of half-moon spectacles. Wear them low on your nose so you can look over them intelligently.
Finish the costume with a long white wig and beard. Both should have straight or wavy hair. In the book Dumbledore's hair is described as being long enough to tuck into his robe. In the films his beard is often tied with a ribbon at his mid-chest.
Begin with an emerald green robe.
Pull your hair back into a tight bun at the nape of your neck.
Add a traditional black pointed witch hat. The films often have the hat bent in the middle with the point to one side.
Finish the costume with a set of square-rimmed spectacles.
Put on flowing black robes. Snape is described in the book as looking like an overgrown bat, so if you want to cut the edges slightly jagged, it will help the look.
Put on a shoulder-length black wig (or use your own hair if it works).
Rub some cooking oil into the hair to make it look greasy.
Apply a sallow shade of make-up to finish the look.