I literally just cut the foam into maybe 2inchx2inch segments (that's for width and height, as far as length I just made it however long I wanted each piece of the hook to be). I then just took an exacto blade and carved the edges way down.
As far as painting: I did two layers of the darkest brown iw anted first, then I drybrushed a lighter brown, and then drybrushed an icy blue. Hope that helps.