Your car will have two grease nipples on each kingpin. I usually turn the steering wheel completely to one side and then to the other. This gives good access whilst lying in front of the car. Some prefer to jack up the front of the car but I have never bothered. Obviously you need something to clean the dirt and any grease from around the nipple. I use paper kitchen towels. For the nipple on the stub axle you can usually see when sufficient greas has been pumped in because some will start to exude around the top of the stub axle. For the nipple that is in the top of the kingpin 4 or 5 pumps should be sufficient.
I usually clean as much as I can the lower spring and the exposed surface of the kingpin then I put a little fresh grease around the spring. Some also use gaiters on the lower rebound springs.