Thoroughly wash the outside of the squash with soap and water. Rinse and dry.
With a small, sharp knife, poke several holes all over the outside of the squash. These will act as air vents.
Cover the slow cooker. For a 3- to 4-pound squash, cook on high for 3 to 4 hours or low for 5 to 6 hours. Add 1 hour (on high) or 1 1/2 hours (on low) for a squash that is 5 pounds or more. All slow cookers are different, so your cooking time may vary depending upon your model.
Check for doneness: firmly and quickly poke the squash with your finger (be careful, it's hot!). If the squash dents easily, it's done (it should not be mushy). See photo above for a visual.
Remove to a cutting board. Once the squash is cool enough to handle, cut off the top and bottom ends, then slice it in half. Scoop out and discard the seeds.
Use any way you like! Fluff with a fork to shred into squash "noodles," use the halves for spaghetti squash boats, or try one of the other suggestions listed in the blog post above. I also like to season my squash with a light pinch of kosher salt.
*If two small squash will fit in your slow cooker side by side, you can cook both at the same time. Whatever squash you choose, ensure your crockpot lid can close completely.
Store leftover cooked squash halves (fluffed or unfluffed) in the refrigerator for up to 4 days. Reheat and use as desired.