Just sharing a story from several days ago. We carved our family pumpkin and figured - why waste the seeds?
We rinsed off the seeds to clean all gunk off them. Then we laid them out in a single layer overnight to dry. (You could dry them first at 300 F in the oven if you like)
After our overnight dry, we preheated the oven to 300 degrees F. Then when ready we put them in for 20 minutes and they were perfect. To season I didn't even use any oil - just generous amounts of salt and garlic.