Braiding eight cords into a flat braid

Step 13: Left - over, under, over. Right - under, over, under, over

Looking at another way, take the left most cord (gray) and put it over, under and over.
Take the right most cord (blue) and put it under, over, under, over over the gray.
The colors are now black, black, gray, blue, gray, blue, black, black.