We have had questions about what to do if bitten by a rattlesnake, but this question, about copperheads specifically, is different because (a) copperheads are less deadly than rattlesnakes; and (b) copperheads are suburban snakes.
Copperheads are much on the minds of people in my area of quasi-rural Virginia these days because the claim is that they are more numerous than usual this year because of the enormous number of 17-year cicadas this cycle. I don't know if this claim of copperhead abundance is true. It is more likely that copperheads seem more abundant because the cicada feast is everywhere -- on lawns, gardens, porches, driveways, walkways, trails -- not tucked away in the woods.
The answer should focus on what to do if bitten by a copperhead while one is alone and also should take into account the time it would take for the bitten person to walk to her car plus drive to a walk-in clinic. For example, it would take me ten minutes to drive to a walk in clinic from my house, but if I were on one of my local favorite trails, possibly over an hour to limp out and drive to the clinic.
Until the cicadas are gone, my strategy is not to be alone while working in places where I do not have a clear view, but then the question becomes trivialless crucial.