oneself
自 centers on the self: one's own person, actions, or nature. It expresses the idea of oneself, personally, or spontaneously.
myself; yourself; oneself; himself; herself
(one's) self; oneself; yourself; himself; herself
freedom; liberty
nature
automatic
self; oneself
itself
oneself
self-confidence; confidence (in oneself)
car; automobile; motorcar; motor vehicle; auto
suicide
bicycle; bike
one's home; one's house
original; unique; distinctive; characteristic; peculiar
Japan Self-Defense Forces; JSDF
pride (in one's achievements, possessions, etc.); self-praise; boast
Liberal Democratic Party; LDP
self-government; autonomy
municipality; local government; self-governing body; autonomous body
self-consciousness; self-awareness
independence; autonomy; self-reliance
one's company; company one works for
one's own work; making by oneself
self-proclaimed; self-professed; self-styled; would-be
自 originated as a pictograph of a nose. In ancient Chinese, pointing to one's nose was a way to indicate oneself, leading to the meaning 'self'.
Picture a person pointing to their own nose to say 'me' or 'myself'. The shape 自 looks like a nose with a bridge and nostrils, so it means oneself.
For ジ, imagine a person pointing to their nose and saying 'Gee, it's me!' The 'Gee' sound cues ジ and ties to the self-pointing gesture.