To be truthful this glitch is useless but it is fun to watch you character run about with an "!" above his head.
What you do is perform a sign like middle finger (or one that you can make last longer by holding the button down) then perform a will move like

Beserk or

Assasin rush (i dnt no if others work), to take it of just do another sign.
p.s i dnt no if this works on fable tlc i have just done it on the original.