I have been looking for this for a long time. I finally just Googled it…
“Right-click the selection you want to have the date picker show up for (i.e. single cell, entire row, entire column) and then open data validation. Set criteria to A valid date and click Save. Now just double-click the cell!” Here it is!
1. Right-click selection area, select Data Validation, set to “Date”.
- 2. Double-click the cell and up pops the date picker!
– See more at: http://bennydesk.com/how-to-add-a-date-picker-to-a-google-spreadsheet/#sthash.RIBJFuGt.dpuf