OK, maybe you won't all need to know about working with stage blood. But many of my followers do Renn Faires, Murder Mystery's and the like, so here is a good article on the topic of fake blood. Also some good advice on acting with it!
http://www.backstage.com/bso/news-and-features-features/tips-for-working-with-fake-blood-1005304082.story
J.T. Turner
The Actors Sensei