I've seen a few other boonie hats with cord in a crossing effect around the hat, but I don't think they started out with trying a two bight turks head knot, as I was intending, worked around the branch loops, on this tiger stripe camo boonie hat.
After tying/untying about a half dozen times, I ended up with just using the first couple of spiraling wraps around the hat, first in one direction, then the other, for the crossing effect. The remainder of the cord was worked around the hat a couple of times, underneath the crossings to finish.
I middled the 22 foot length of paracord when I started, to reduce the work of wrapping the cord, and so I only had to go around the hat about 4 times. If the cord is needed for some reason, it's not hard or time consuming to remove it, and it won't be all kinked up, like some other methods of tying.
The over hand knot, tucked through the hat's leather chin strap toggle, is where I started the hat band, and the center looped end of the cord, was tucked under the crossings, a little past the back center of the hat.
I added a YouTube video for this method of adding some paracord to a boonie hat, shown using a longer 30 foot length.