Preheat the oven to about 180 C. Take one potato - this made enough to satisfy my craving. Cut it into slices, as thin and regular as you can. I'm not super expert at this, as you'll see below. If you have a mandoline it'll be a lot easier and quicker but I don't (yet!) and it still didn't take too long. Thinly coat a baking sheet with olive oil and lay the chips in a single layer, then sprinkle the top with oil also. I have a spray bottle but it's a bit hit and miss, so some of mine drowned in oil while others missed out entirely. Oh well...
To flavour, use whatever spices (or indeed anything else) you wish. I went with good old salt and pepper, but I've heard curry works well, as would many other spices - maybe a bit of chilli powder if you're after a kick, or you could even use powdered chicken stock if you want to replicate the fakey-chicken flavour of bought chips.
Put them in the oven for about 10 minutes, but watch closely. You want them to start to brown, but not get too dark. When they're beginning to look mostly cooked turn them over and cook for another 8 or so minutes. Because they are so thin you do have to watch pretty closely.
You can also cook these in the microwave - I've done this before too. The same applies for oil and flavour, and just lay them out on a piece of baking paper to fit in your microwave (take the plate out so it doesn't turn). Then cook for about a minute - you definitely need to watch these like a hawk, though, and I found it was a bit more labour intensive, as a) I couldn't do the whole lot at once and b) I found some cooked really quickly and I had to remove them before they combusted, meaning lots of stopping and starting. Quicker result, though!