Place it at the end of a setup clip, right where the bad idea is revealed, then follow it with Nope for a double refusal that closes the scene. Put Okay Let's Go before it when you want the contrast between agreement and the sudden change of mind.
About this sound
This is a short spoken refusal lasting just under ten seconds, centred on a single fast no delivered without hesitation. It feels blunt, dismissive and a little comic, the kind of reply that shuts a suggestion down before it can grow. Its abruptness makes the rejection feel final rather than angry, leaving no room for a follow-up.