I'm new to Sublime. How do I set the option trimTrailingWhiteSpaceOnSave.
I've tried using the console, but failed.
It's in your settings file. Go to Preferences > File Settings - Default. You can also get to this file by using the Command Palette (windows: ctrl+shift+p; mac: command+shift+p) and typing "Default File Settings." Inside is a list of all the settings. Scroll down until you see: "trim_automatic_white_space." Set this to true.
You might have been looking for following option, instead:
// Set to true to removing trailing white space on save