Preheat the oven to 350°F.
Remove the seeds. (If using a sugar pumpkin, cut the pumpkin in half. If using a larger carving pumpkin, cut a hole around the stem and remove it.) Scoop out the seeds and the majority of the stringy bits and add to a colander in the sink.
Rinse and pat dry. Run water over the seeds and discard the stringy bits. Shake off as much excess water off the seeds as you can and then pat them dry with a clean kitchen towel (the drier the better for crispiness).
Season. Add the seeds to a baking sheet and toss with just enough olive oil to coat the seeds, salt, and any additional seasonings.
Bake. Spread the seeds out into an even layer on the baking sheet and roast 15-20 minutes, stirring every 5 minutes to prevent burning and for even crisping.
Let cool. Let the pumpkin seeds cool down before enjoying and storing them.