Allison Janney and Sam Rockwell discussed the difficulty of laughing and crying on cue during their interview for Variety‘s “Actors on Actors.”

The pair cited late actress Britney Murphy as an example of someone who could turn her crying on and off at the flick of a switch, and lamented their difficulties doing so. Janney said she’s mastered being able to laugh on cue, however, and explained that it all starts with the physical movement of the diaphragm.

“I had to laugh on stage hysterically every night,” Janney said. “It was like, ‘Ugh, I don’t want to do this anymore,’ and someone said, ‘Just start ‘huh,’ start from your stomach going, ‘huh, huh, huh.” So just the physical act of laughing, and then it gets real.”

Rockwell offered his slightly less conventional technique of using a fart app on his phone to make himself laugh.

The seventh season of Variety’s “Actors on Actors,” presented by Google Home, will air from Jan. 2 to Jan. 4 at 7 p.m. on PBS SoCal KOCE.