You could do it old school with a compass and a pace count. My pace count is about 10 paces (two steps per pace) to a chain (66 feet). So that's 15 paces every 100 feet. Just go from tree to tree with a bearing and a distance. It'll be kind of like a treasure map for you and each time you find your standing dead marked tree, you win the prize of getting to go to work.
Another way to do it is to identify a center point for each acre and clearly mark with a pan orange post. Then you take a bearing and distance to each tree you want to cut in that one acre compartment. A square acre being 208' per side, the furthest distance from the center would be to a corner of the square at 147'. GPS would be good to locate the center of each compartment.
So I spray paint the trees blue, cut em with a Hatchet, put survey tape on them, take a selfie with em, mark em on gps, find em with a compass and mark that on a baking pan and nail a $100 bill on them! I think that will work.
Drive a bunch of nails the trees to ID them...then you can find them with a metal detector...if that don't work, just fire up your saw...that never fails to find logs with nails...
I do it backward. Mark the trees I'm keeping as crop trees with that brightly colored ribbon stuff (what's that called?). Then as I'm thinning, I can easily see which trees to makes sure don't get collateral damage. Once the keepers are marked I'm checking the canopy and "releasing" it for faster growth by cutting non marked trees whose canopy is touching a keeper.
I used gps to mark game camera locations. They are being used as ginseng poacher cameras now, later in the season they get converted to game cameras.