Watch the Keeping It Straight online guitar lesson by Angus Clark from Focus On: British Metal
This lesson is two in one. You'll want to focus on keeping your straight time down stokes in time and accurate. You will also want to make sure you are in complete control of how you mute the strings with your right hand. Make sure you are using a convincing amount of gain on your amp so that your technique is up to the task. Distortion won't cover for you in this context.