Either you must provide the reason it is evidence for god or it must be already understood that we both understand why it is.
This is frankly rather absurd. Your remark proves my point I think.
The point of course is that you have no logical process to ascertain true evidence for God, you have a
precondition that involves other people.
By definition, as written above, you require a person to present a reason why they regard the evidence as evidence in addition to said evidence.
Very clearly - if God does actually exist and if there is evidence for that, you would
never be able to independently discover that because you need some prior individual to provide a "reason".
I'm satisfied that you are logically adrift here, this should be clear after my numerous replies but if not then you have a true problem with epistemology and once again make a very poor case for atheism.
Take the hoofprints on the prairies example. If we both live on the prairies and clearly already know what hoofprints look like no further explanation is required if not then you must include photos or links to photos of known hoofprints or provide some other means of showing that your evidence it what you claim.
After that we can move on to discussing is it evidence of Horses or Zebras. It still however will not be evidence of unicorns
Which should be included with your evidence.
What if you were alone and had never seen hoof prints before and had never seen an animal capable of making them, how would you interpret what you saw on the ground?
By definition - based on everything you've just said - you are
incapable of recognizing the evidence because you have no test you can apply, this is exactly what I said at the outset.
Perhaps we should be discussing two separate questions:
1. How does the atheist decide if something they personally encounter is or is not evidence for God?
2. How does the atheist decide if a person claiming something is evidence for God is telling the truth?
This is perhaps a better approach if we are to continue this, we've covered 2. I think, so what of 1.?
(I know that Hitchens would have struggled had I confronted him like this, so don't feel too bad if your head is swimming)