No, didn't shell them. Just wiped most of the gunk off (no need to rinse - in fact some people say it is a positively bad idea to rinse as you lose some of the flavour), mixed them up with a bit of melted butter, sprinkled with some spices (we used salt, celery salt and smoked paprika, which worked well but it is up to you: cumin might be nice) and then spread them out on a baking tray, taking care to make sure they were in a single layer. Moderate oven for (very roughly) a quarter of an hour: the timing is very much up to you and your oven, but I think you want the seeds lightly toasted. Again, that is a matter of taste: some people might prefer them well done.