Click on Main Menu>Settings>System Options>Customer Display.
If you are NOT using a Customer Touch Display, you do not need to worry about either of these settings.
If you are using a CTD, you can turn on Sign By Finger, which allows your customers to use their finger to sign on the CTD itself instead of on the paper receipt.
By toggling on the Tips option, you’d allow customers to add a tip by using the CTD before signing their receipt.
Make sure to click Save Changes when finished.