Wiccan/Pagan protective forking of the hands?

In 'Chocolat' by Joanne Harris, the protagonist is a woman of unspecified pagan beliefs, and she has a habit of surreptitiously 'forking' her hands/fingers towards her enemies to repel them and dispel any evil intentions or negative energy. It isn't made clear exactly what the hands are supposed to look like when she forks, are the fingers splayed, or held out like a Vulcan sign, bullhorns, or something else?