How do I get an audio clip to play at a specific time?

I'm trying to get a sound to play at a specific time after my scene starts for one of the Unity tutorials. I've used some script that I found on one of the forums but it doesn't seem to work, it just plays as soon as it starts. I am very new to this, so it's probably something obvious. Also not very sure on the conventions for asking things on here so let me know what else to add/ not include.

Thank you.z