Heat the oven to 250 degrees F and put a rack in the middle of the oven. Peel the squash and cut it in two, separating the thin end without seeds from the bulbous end. Scoop out the seeds with a spoon and discard them (or save and roast them if you're feeling energetic).
Slice the squash finely with a mandoline, about an 1/8-inch thick. You'll have nice neat rounds from the seedless end, and pretty rings from the other end.
Toss the squash in a bowl with the herbs, olive oil and salt. Line 2 baking sheets with parchment and spread out the squash slices in a single layer on the parchment. Bake for an hour, then flip the slices using tongs or a spatula. Bake for another hour. Turn the slices again, lower the heat to 200 degrees and bake for another hour. Turn off the oven and let the chips cool in there for several hours, or overnight. Remove from the parchment and serve, or store in an airtight container for up to a week.