Neigong is a focus. It is like a koan.

It pays attention to how an action is performed rather than the action itself.

Imagine throwing a punch?
Neigong addresses what the body does in order to produce the punch.
It re-trains the framework to deliver power from the whole-unit rather than the shoulder, waist and leg.

Each neigong is different. It has a particular emphasis.
Neigong is internal, with most of the work occurring unseen.
The body looks to undulate as you move.

Fa jing is not hard, it is soft. The effect is hard, not the means itself.

No more than 4 ounces of pressure is applied and the moment of delivery is a split-second.
You do not have time to tense the hand.
The hand (and body) must close by itself on impact, then instantly re-open again.
Conscious strength ruins any chance you have at using fa jing, so just relax.
Be patient.

When you deliver fa jing into a focus mitt or target pad it will pass through the body and into the ground. 
It may cause the floorboards to resonate.

Reach is the act of stretching out your arm or leg in order to touch or grasp something.
It is the limit of your potential stretch. 

A young boy travelled across Japan to the school of a famous martial artist.

When he arrived at the dojo he was given an audience by the sensei.

"What do you wish from me?" the master asked.

"I wish to be your student and become the finest karateka in the land," the boy replied.

"How long must I study?"

"Ten years at least," the master answered.

"Ten years is a long time," said the boy.

"What if I studied twice as hard as all your other students?"

"Twenty years," replied the master.

"Twenty years! What if I practice day and night with all my effort?"

"Thirty years," was the master's reply.

"How is it that each time I say I will work harder, you tell me that it will take longer?" the boy asked.

"The answer is clear. When one eye is fixed upon your destination, there is only one eye left with which to find the way."

(Joe Hyams)