Before passing another vehicle on the right, it is crucial to ensure that the vehicle is preparing to turn left and that there is adequate room on the main traveled portion of the road for the pass without leaving the pavement. This ensures the maneuver is completed safely and within legal boundaries without forcing either vehicle off the paved road and into potential hazards. This rule is detailed in the 'new-york-car-en.pdf' to ensure drivers only pass on the right under safe and legal conditions.