1) a REAL WITCH is certain always to be wearing gloves when you meet her even in the summer, even in the house and only take them off when they go to bed. This is because she doesn't have fingernails; she has thin curvy claws like a cat and she wears the gloves to hide them.
2) a REAL WITCH is always bald as a boiled egg and wears a first-class wig made from ordinary hair to hide her baldness. Look out for wig rash.
3) a REAL WITCH has the most amazing powers of smell and have slightly larger nose-holes than ordinary people. The rim of each nose is pink and curvy, like the rim of a certain kind of seashell. The cleaner you happen to be, the more smelly you are to a witch. An absolutely clean child gives off the most ghastly stench to a witch. The dirtier you are, the less you smell. Grown-ups don't give out stink waves, only children do that.
4) a REAL WITCH's eyes are different from ordinary people. Their pupils will keep changing colour; you will see fire and you will see ice dancing right in the centre.
5) a REAL WITCH never has toes on their feet; the feet have square ends and witches hide their ugly feet by wearing small pointed shoes.
6) a REAL WITCH has blue spit; blue as a bilberry. If you looked very carefully, you would probably see a slight blueish tinge her teeth.
If she has all these things, run like mad!
* Information derived from The Witches written by Roald Dahl *