I love spaghetti squash! As a veggie side dish or as a main dish subbing in for pasta! While it doesn't taste just like pasta, it's a wonderful, healthier alternative and very easy to make.  Here's how I do it:

I cut the squash in half lengthwise. With a spoon scrape out the seeds from the middle.  Brush the cut side with olive oil and place cut side down on a baking sheet lined with foil or parchment paper.

I roast the squash in a 350-375 degree oven for about 30-45 minutes, depending on the size (and depending on your particular oven). 

The skin will get golden brown and it will easily give when gently squeezed or poked.

Remove from oven and let cool slightly. Hold in a kitchen towel skin side down so you don't burn your hand and with a fork, gently scrape the squash creating the strands and put into a serving bowl. At this point you can season it any way you like, add your favorite pasta sauce or simply granulated garlic and more olive oil.

It really is delicious.  My son Chris likes it combined with quinoa and seasons it with turmeric, black pepper and cumin.