car if misfiring

What is your question?

I'm changed the spark plugs, and the car still misfires in the morning when I first start the car. I have to turn it off and on about 5 to 10 times before the car starts up running normal. If I drive the car over 10 minutes I can cut the car off and it starts up just fine. This problem of misfiring only happens when I cut the car off and it sit for a long period of time. I need help fixing this problem