This last weekend in Iowa I saw several peole hunting without a dog. Another approach would be to follow creeks or streams. The birds will tend to run, but any flowing piece of water will turn and sort of double back on itself making a "P" shape. Once the birds run into the "loop" of the "P" they will sit tight and tend to flush easier when you approach. I watched it work once this last weekend so I know it works. Good luck.