自 is "eye" plus a dot, which we'll call a splinter.
to do something one's own self, in person
one's own (dog, blunt, fungus, etc.) - BOOBOO: sometimes it also is used to mean "you" or "she", as in "She did it herself, as opposed to having others do it for her."
Japan's army, in English called the SDF (self-defense forces)