Did they change the design?
On my 2011, the adjustment consists of rotating the collar that supports the rear spring. It has some grooves cut into it for the tool to latch onto but if you don't have a tool, using a short metal rod and a mallet to drive it can easily rotate the adjuster.
The bike has to be on the center stand when your doing this so the springs will be as "unloaded" as possible.
Like some in this post have mentioned, some just grab ahold of the adjustment collar and twist it with their hand. (Lubricating the cam ramps helps).