How to make wafer paper?
As recipe writing is off-topic here, the starting point to reduce the parameters is to look for recipes containing "Sacramental bread recipe", "unleavened communion bread recipe", or even "edible paper recipe".

Just ensure to enclose the search items in-between double quotes (copy-paste the search terms above) and if you find a real church recipe, substitute the biblical grains like Spelt, Khorasan_wheat, ... by organic white flour without any additives if you cannot find the original easily and use a little less water.