Fellas, I'm a long time digger. Sometime I think I got some old yard dog in me. Here in Texas may be a bit different than by ya'll , but the game is the same. It's all very elementary. Start by getting on your hands and knees (good knee pads pay off) and scrape the area in an ever widening radius. Clear enough space for you to turn 360 degrees and then some. If your gonna start going down, first clear a spot where your throw dirt is gonna land so you don't cover any thing good up, or throw down a vinyl tarp. I like to sift my throw dirt thru a 1/4 inch screen so if you want to do the same clear an area for that. You don't want to cover an area with throw dirt if it's holding artifacts underneath.
Start going down about a shevel deep about fox hole size and watch the dirt for clues to the direction to go. Expand sideways as needed. Burnt and crystalized earth, bone debris, flint, etc. all tell tales of usage. Generally we go to virgin earth. Some places its caliche, some places Grey or tan clay. It's easy to be fooled by a sand line down deep. It could have happened due to a flood thousands of years after it was used, and there may be stuff underneath. I use a couple of probs I made to feel for camp rock and midden fill so I don't get fooled. Near Austin I was down almost 6 feet and I hit crystalized earth under a few inches of sand. I found a 4 1/2 inch Nolan (with a twist) facing up against a fire rock. I almost nailed it dead on w/ my pick, and saw it at the last second. Good luck G.