No, that's not a typo - this is the third in my grow your own series - Potato chitting is one of those things that some grow-your-own types like and others don't. Remember the last lot of potatoes you bought, stuck in a cupboard and forgot about? Well chitting is the same kind of thing. The potato starts growing in the nice cool windowsill you've got, then you can transplant outside.
1) Potatoes - not just any though!
2) egg box
4) 'special knowledge' (you'll get that in a minute...)
Step 1: Buying the potatoes
This is bizarrely an important step - why? That's because normal store bought potatoes will usually be OK, but may possibly contain disease you don't want to put into your soil. Use 'seed' potatoes from the local nursery or seed store and you can guarantee they will be virus free. That's not to say that the soil you're putting them in is disease free, but at least they'll have a fighting chance.
You can pick them up fairly cheaply from a good shop - mine here cost Â£2 from the local nursery
More importantly is that you can often pick up varieties of potato not usually available or even endangered or rare plants - though often these are sold as actual plants rather than the rare and valuable tubers.