Upgrade it to the second level of Phasic Cloaking, put the Navigator at a star, disable autocast, and use Phasic Cloaking. Since the star regenerates AM faster than Phasic Cloaking consumes it (2.5/sec restored versus 2.0/sec consumed), the Navigator can never be destroyed until you pull it out and you have effectively permanent visibility of the star.
However, outside of that, Phasic Cloaking only prolongs the lifetime of your scout by a few seconds if frigates are around.
In a grav well with only strike craft to worry about, activate Cloaking just before the SC's weapons fire, and deactivate once they finish their pass.
