Also called "Water Gold and Water Through", these points are amazing for asthma. The name threw me off a little until I heard Dr. Robert Chu say that the water part is about the Kidneys, which have a crucial role in holding and extracting nutrition from breath. The "gold" part is how great the points are and the "through" part refers to how it's needled. Read on.
To locate these points:
Shui Tong: 0.4 cun distal from the lateral corner of the mouth.
Shui Jin: 0.5 cun distal and medial from Shui Tong.
These are generally needled from Shui Jin upward and diagonal to Shui Tong. You don't have to get out a measuring tape and be an engineer to find these points. Look for a dark or purplish area in this zone and start needling there.
This excellent video from eLotus is a good visual to understand this.