Wash the spaghetti squash with warm soapy water and dry it with a clean kitchen towel.
On a flat surface, carefully slice it lengthwise and with a spoon, scrape the seeds out and discard. Pierce the skin of the squash with a sharp knife -this helps the heat go through the squash layers.
Cook the spaghetti squash:
Place the spaghetti squash halves in the slow cooker and pour in the water.
Cook it on high for 3 to 4 hours or low for 7 to 8 hours, until the meat separates easily from the skin with a fork.
When ready to serve, remove the squash from the slow cooker dish onto a cutting board, and with a fork, separate the squash shreds from the skin and transfer them onto a plate. Top it with your favorite sauces or use it in a recipe.