Add 1 teaspoon flour to a plastic bowl. Make sure that the flour is properly sifted. Pour 1/2 teaspoon red food colouring on the flour and mix the contents of the bowl. Flour serves as a thickening agent and thickens the fake blood to give it a more real look. If you do not have flour, you can use cornstarch instead.
Apply a uniform layer of cooking spray on the tablespoon you are using. With this cooking-spray-coated tablespoon, add 1 tablespoon corn syrup to the contents of the bowl. Cooking spray prevents the corn syrup from sticking to the tablespoon. Remember to use just a small quantity of cooking spray to avoid adding too much oil to the mixture.
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Now you need to add a very tiny drop of blue food colouring to the mixture in the plastic bowl. Use a toothpick for the job. If you need to give the fake blood a more purple touch, you can add the same amount of green food colouring to the mixture.
Only red food colouring is too bright and will give a fake look. You need to use the blue and green food colourings to give the blood a more real look.
Now it comes to the minor adjustments. You can use additional food colouring to make adjustments to the colour of the fake blood. If you want to adjust its thickness, you can either use water or chocolate sauce. Adding water will make the blood thin while adding chocolate sauce will make it thick. Remember that using chocolate sauce will give a darker shade to the blood. If you want the fake blood to retain a brighter colour, use flour or cornstarch. Finally, you need to make sure that it is easy to remove the fake blood stains from clothing even after they have dried. You can add a few drops of liquid laundry detergent to make sure fake blood stains are easy to remove from clothing.
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