Making potato chips is sinfully easy. Just wash them well and trim off any spots....or peel them, if you prefer. Slice them on a mandolin, or as we do, on the slicing blade on our box-style cheese grater. Watch your fingers! You can save the last chunk that you can't slice and cut it into French fries.
Put the raw chips in a large bowl and run cold water into it. Stir gently with your hand. Change the water and repeat until the water is clear, then soak them for a couple of hours or more. Stir and change the water periodically if needed, if it is ever cloudy again.
Then drain in a colander, and pat them dry carefully. I then spread them out on kitchen towels, layering them on top of each other to save space on my counter. The longer you let them dry, the crispier your chips will be.
Heat some tallow or lard just until it starts to smoke a little, then add a couple of handfuls of the chips, and stir to spread them out in the fat. Don't crowd them too much. Use a splatter guard if you are not using a frying machine. I use my big Dutch oven, but before I had it, I'd use my biggest cast iron frying pan.
Let them cook for a few minutes, until you see them start to brown lightly. Scoop them out with a skimmer (large flat "spoon" made of wire mesh, or just a big flat metal spoon with holes) or use a couple of slotted spoons to get them out and onto layers of paper towels or crumbled and smoothed brown paper bags, cut open and using the unprinted side. Salt well. Add the next batch to the hot oil and try not to eat all of the ones that are cooling!