Keyboard shortcuts for Gmail

Shortcut Key     Definition     Action
Ctrl + Enter
Mac: ⌘ + Enter     Send message     After composing your message, use this combination to send it.
Ctrl + .
Mac: ⌘ + .     Advance to next window     Use this shortcut to move the cursor to the next chat or compose window, or to the main window.
Ctrl + ,
Mac: ⌘ + ,     Go to previous window     Use this shortcut to move the cursor to the previous chat or compose window, or to the main window.
Ctrl + Shift + c
Mac: ⌘ + Shift + c     Add Cc recipients     While composing, takes you to the Cc field to add new recipients.
Ctrl + Shift + b
Mac: ⌘ + Shift + b     Add Bcc recipients     While composing, takes you to the Bcc field to add new blind recipients.
Ctrl + Shift + f
Mac: ⌘ + Shift + f     Change "from" address     While composing, takes you to the From field to change your sending address. This shortcut only works if you have configured additional sending addresses.