This way is very easy and it will never really backfire on you. You have your defensive line. Take a guy from one side. I usually take the Right End and move him over outside of the Left End. It works either way if you wanna move the Left End. Anyway now if there is no Tight End you can just get right in there and disrupt or sack the QB. Even if there is a Tight End on that side he is way easier to plow over than the lineman that you line up against at the start. The only way this will backfire is if they run the ball to the side that you just left open. Then there is one less guy to make a tackle and the CPU can get more yards or even a touchdown but if you have good DB's and LB's you should be fine.
On the main menu go to roster. After that go to 'Edit Player'. Pick a player you want to edit. And then move the OVR button to the SPD button and push X on it and move the speed creation points to 99 points and push X again.