1. Go over to effects and search for transform and drag it onto your clip
2. Now move your timeline slider to where you want to begin the shake effect
3. Under effect controls - Scroll down and click the stopwatch icon beside skew axis
4. Modify the value of skew to 4 - then move your timeline slider ahead a few seconds and increase the value of skew axis to a large amount
5. If you want to add more or less shake - simply modify the value of skew under transform to a different value
