You'll probably bog down on the treadmill. Get out on the streets and run. You'll see other joggers. See if you can catch them. It speeds you up. If you don't see any then pick out a telegraph pole or a parked car and see how fast you can run till you get to it. Slow down to a more gentle jog for a bit then sprint again to the next one.
It's a form of interval training (which you should Google if you're serious about getting faster. Good luck. When you get used to it you'll start to enjoy it.