Heat the squash in the microwave for a minute or so to soften it. Then cut the squash in half.
Take all the "guts" out of it. The seeds and most of the stringy parts. If some are left that is fine, they are edible so don't worry. Once you do that, place both halves face down into a microwave safe dish that has about an inch of water in it. Microwave for about 10 minutes.
Be careful removing the squash from the microwave, it will be very hot. Let the halves cool a little after taking them out of the dish. Once cooled, take a fork and start to scrape the squash. Doing this will make the squash look like it's spaghetti.
This is what the squash will look like when it's been scraped enough and the result of what was scraped.