The hit and run is a response to a situation where you're threatened, cannot escape without attacking, but can attack and then quickly flee. For example, if you're alone (thus you won't be leaving a loved one behind), cornered, and close to safety, a hit and run may be the perfect option. It also works to create space to access a weapon, or give you the opportunity to attack further if necessary.
Practice the hit and run by having a partner approach you in a threatening manner, where you quickly use your preferred technique with footwork that moves you offline in such a way that you can sprint off immediately after the initial attack.
Many techniques can be used for the hit and run. What's important is that accompanying footwork puts you in a position to escape, and the technique keeps you covered in case the attacker launches an attack as you do. Two of my favorite techniques for the hit and run are the eye strike and the groin slap. Here is the eye strike, below:
See more self defense techniques, or more from the Fundamental Five: