Are you asking how many teaspoons of Cayenne powder to a teaspoon of flakes?
I never measure either, I go entirely by taste as the age of the spice affects the flavour. I also blend various pepper powders, such a Cayenne, Chipotle, Smoked Paprika, Ancho etc.
I find using a variety of peppers gives depth of flavour without too much spice.
You can also soak the flakes in one of your liquid ingredients and whiz it in the blender.