Question: how to change the date in garmin forerunner 235?
Answer: Press the "Power" button to turn the device on while standing outside. ... 
Select "Settings," "General" and "Time" from the main menu.
Select the "Time-Format" drop-down menu, then set the time to display in 12-hour or 24-hour format.
Choose "Time Zone" and choose your time zone from the drop-down menu.