Sending full system log for macOS 10.9 - 10.11
If you need to send the whole day's console log then open the Apple Console app by typing console into Spotlight search.
Select All Messages on the left hand side and then in the File menu choose Save a Copy As...
Before saving make sure that the date range shown at the bottom of the Console covers the correct time range, if not use the Earlier button. Or perform a log query as described below. Save to the Desktop and then send this file to firstname.lastname@example.org