This line loads the extra style definition:
* Set USERSTYLEURL = %PUBURLPATH{topic="%SYSTEMWEB%.PatternSkinCssCookbookSidebarToggle" "SidebarToggle.css"}%
To activate the button in the sidebar, override the
viewsidebar.pattern.tmpl
using the supplied
viewsidebar.sidetoggle.tmpl
by adding it to the front of
the SKIN setting.
Your current SKIN setting is
natedit,pattern
Change it to
* Set SKIN=sidetoggle,natedit,pattern
The formating and positioning is done in the css. When the sidebar is hidden, the button will appear in the lower left corner of the screen, appearing as the "hamburg" icon: ...
.