I have several pairs of Chanel boots, flats, and heels and I always wear 1/2 size up as Chanel tends to run small.
+1
it seems that my Chanel shoes or boots always need to be sized up from my real size 6. 36 is usually snug, though I do own one size 36 pair of boots because the 37's are literally one inch too large. Unfortunately, in Chanel (and Prada, too) I find European sizing to be a farce.
Let us see what you end up with

