Take a sip if you or someone else accidentally triggers a car alarm.
Take two sips if you or someone else shoots it on purpose.
Finish the glass if all of the alarms are triggered in The Parish's Cemetery level.
Take a sip every time a survivor says "Grabbing Pills!"
Take a sip for every friendly fire incident you suffer from other players. Two sips if it results in a player being down and finish the glass if the friendly fire causes a player to die. Not recommended to try on Expert mode!