Hold the pumpkin firmly in one hand and with your other hand snap off the stalk if present. Place the pumpkin on a flat work surface and with a sharp knife carefully cut the pumpkin in half.
Using a spoon to help you, scoop out the seeds and fibrous centre of the pumpkin and place on a chopping board. Separate the seeds from the fibrous pulp and place in a sieve.
Run the seeds under the cold tap giving them a good rinse. Spread the washed pumpkin seeds out over several layers of kitchen paper then place a piece of kitchen paper on top and pat dry. Place the seeds in a cool, dry spot until ready to use.