Originally Posted by hippofeet
A picture would be a big help here. in general, I guess I would sew a box of stitch in the body of the bag, where you want the hole to be, leaving a hem allowance, cut a slit in the box in the shape of an elongated H, fold and hem for clean edges. then I would sew on some Velcro, and a flap so I could close the hole when not on the hammock. If there is a seam in place at the foot of the bag, I would rip the seam, and stitch the material seperately.
I am at work right now but I will post a photo when I get home. Basically it's like a pocket for a foot warmer or something. It doesn't need to be a really clean looking opening, as you won't see it because the foot pocket would be zipped up unless it's on the hammock.