How can I make fake blood for a movie?

Question by laser_vamp: How can I make fake blood for a movie?
Ok, I want to make fake blood for a gory movie; I also would like to know how can I do the following scene:
At a first person perspective, the killer will cut someone’s throat from behind. How can I make the blood come out gushing disgustingly AND without revealing the trick? (making it look “realistic”)
Oh, by the way, if it doesn’t permanently stain clothes, it would be much better.

Best answer:

Answer by doggie lover
Ketchup or water with red dye in it.

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