Worst UI ever!
Here is the charging screen:
To set Scheduled Charging (the Tesla vehicle will start charging at a specific time each evening) tap on the word "Switch" in the label "Switch to Scheduled Charging". Now the Charging Screen should look like this:
Slide the slider button to the right, the Scheduled Charge Start time should appear in bold text, look like this after you enter the desired Start Time:
The terminology used on the Charging Screen settings is worse than the UI:
Scheduled Departure - The Tesla vehicle will charge during the off-peak utility rate period, either complete charging or stop charging by the end of the off-peak period. (If you have more than one off-peak utility rate period each day you have to pick one off-peak rate period. This will probably be the off-peak rate period that starts somewhere around midnight and ends somewhere around 6:00 AM (your local time.)
Set Off-Peak Hours - This sets the end time for your Off-Peak Utility Rate Window; this is most likely 6:00 AM but you can enter any time. (The Tesla vehicle will try and charge while the utility rates are lowest.)
Set Scheduled Departure Time - This is the time you normally leave, drive the Tesla vehicle. You can only enter one Scheduled Departure Time.
Set Preconditioning On - The Tesla vehicle will use the Scheduled Departure Time to start preconditioning the Tesla vehicle. Preconditioning will start shortly before the Scheduled Departure time to warm up the battery in cold weather and either warm or cool the passenger cabin depending on how you have the climate control set. (Note: The Tesla vehicle does not have to be plugged in to use Scheduled Departure, Preconditioning. As long as the battery state of charge is above 20% the Tesla vehicle will precondition the vehicle if Scheduled Departure Preconditioning is set to On. (On the Scheduled Departure Settings Screen you can specify whether Preconditioning happens All Week at the same time (based on the set Scheduled Departure Time) or just on Weekdays (Monday through Friday.)