In GWX you get Renown for:
200 points for reaching your assigned grid
200 points for patrolling your assigned grid for 24 hours
100 points for docking at your home base (being within about 25km of port and selecting "Dock at" option, as opposed to using the "Return to base" option, which teleports you to base from anywhere).
The following link has a chart listing the Renown you get for sinking different types of ships in GWX:
http://files.filefront.com/GWX_renow.../fileinfo.html
The Renown points you ACTUALLY get are modified by the Multiplier in this formula:
Multiplier = 0.25 + 0.75 x [your percent of realism setting]