How does the Ego (responsible brain) gain control of the Id (immature brain) if the Id has complete control?

Freud wrote of the defense mechanisms this is how the ego controls the id...there are many...repression, sublimation, projection, intellectualization, etc. etc....some were good, some not...all are not if used to excess. BUT this is how the id is controlled. The person learns that needs cannot be satisfied according to the pleasure principle, so with the growth of the ego, the reality principle comes into play...all to gratify needs, but with regard to the external world and with a delay in gratification. Remember the unconscious always "rears up" in distorted ways...the person is just not aware of the motivation....so how to get back to control? Well...Sigmund of course would say, "lots of psychotherapy"...drugs to release the unconscious (he was a cocaine addict...not known at the time it was addictive"...Freudians today use projective techniques..anything to release the unconscious to understand the motivation of the behavior") That's Freud in a nutshell..(psychology professor)