[Checked QGIS 2.14 / 2.18]
Yet another way is to create a new folder under
C:/Users/your_name/.qgis2 and name it
svg. This new
C:/Users/your_name/.qgis2/svg is automatically recognized by QGIS as the path to pre-defined
User Symbols Group.
Then just copy the downloaded icons into it. The top-level folder (just below
svg) will become the subgroup name.
C:/Users/your_name/.qgis2/svg/MAKI will be:
(Update for QGIS 3.0)
QGIS 3.0 does not use
.qgis2 folder anymore, so the location has to be checked by opening
Settings | User Profiles | Open Active Profile Folder.
svg folder in this location. Then again, QGIS will recognize it as the User's