Coconut flour needs more liquid than other grain flours or gluten - free flours, you'll need 1 cup of liquid for every half cup of coconut flour that you use. (coconutflourpancakes.com)
I haven't tried this recipe using coconut flour, but you could try substituting a 1/3 cup of coconut flour for each cup of almond flour. (eatyourselfskinny.com)
If you want to use just coconut flour for the whole recipe, use 3/4 -1 cup of coconut flour instead of the almond flour. (KetoDietApp.com)