For exact step-by-step diagrams and reset procedures (including how to zero the chronograph hands if misaligned), always consult the official manual specific to the movement caliber printed on the watch case back.
Never set the date between 9:00 PM and 1:00 AM. The internal gears are engaging the date wheel during this period, and forcing it can break the movement. citizen eco drive gn-4w-s-12g manual
Alternatively, if you are in the US or UK, you can use the localized Citizen US Setting Instructions Citizen UK Setting Instructions databases. citizen eco drive gn-4w-s-12g manual
The mark often accompanies a water resistance rating. citizen eco drive gn-4w-s-12g manual