Get a semi-thick liquid and some red and blue food coloring.
Test different degrees of the colors to come up with the perfect blood color.
More red than blue.
And fill up some plastic baggies with the stuff, make sure they don't leak. Then hide them in the costumes, all you need to do now is be able to use a small charge (pyrotechnics) that's also hidden in the costume to make a "gunshot wound" to the clothing, and at the same time pop the bag of "blood". Make sure the actors have sufficent padding between their bodies and the costume so to avoid injury.
How To Make Fake Glass or Sugar Glass (simply called caramel 😉 )
Materials :
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[*] old saucepan
[*] oven
[*] baking thermometer
[*] 2 measures of water
[*] 1 measure of golden syrup
[*] 3 1/2 measures of sugar
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Steps :
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[*] Mix the water, golden syrup and sugar together in the saucepan and bring it to a boil on the oven.
[*] Leave it boiling until the mixture is thick, with almost all the water boiled off.
[*] Pour it into whatever mould you're using and let it cool.
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Notes :
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[*] Keep it out of moist areas and direct sun.
[*] Sugar glass doesn't last long (warps or goes sticky) so make it close to the time when you plan to use it.
[*] Though only sugar, the glass can have sharp edges/points when broken, so be careful when handling.
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