Instructions
Desktop
Go to Calendar from the left navigation bar on desktop. In My Calendars, find the target calendar, click the … icon next to it, choose Change color, and select the color you want.
The calendar will display with the new color.
Open DingTalk on mobile,tap Calendar / Schedule at the top, tap … in the upper-right corner, go to My Calendars, tap … next to the target calendar, tap Change color, select the color you want, and tap OK. The new color will take effect.
