Place it immediately after the boast in an edit, then follow it with a laugh to underline the callout before cutting back to the storyteller's reaction. Keep a yeah ready for the beat after that, when the group starts piling on.
Über diesen Sound
This six-second voice clip delivers the slang callout 'stop cappin' in a blunt, confrontational tone, aimed squarely at someone stretching the truth. It lands as funny and cutting at once, with the swagger of a friend refusing to let a tall tale slide, and it works best as a quick verbal jab rather than a long argument.