With the shield assembled, it’s time to test it out and put it to use. Plug it back into your Arduino, and start up the Arduino development environment.
In the Arduino window, choose the Examples -> Liquid Crystal -> Hello World
Replace this line:
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
With this one:
LiquidCrystal lcd(12, 11, 2, 3, 5, 4);
You can look this up on the PCB itself – What each pin does is written on either side of the jumpers.
Now compile and program the sketch onto the Arduino.
Next, we need to set the contrast. If you can’t see anything on the LCD, turn the white knob in the middle of the pot until it looks right.
You should see something like the image at right. The number is the number of seconds the “Hello, world!” sketch has been running for.
Connecting to non-standard LCD displays
Some LCD displays, for example the Lumex LCR-U01602DSF from Newark, have 
the pins in a non-standard order. They are left shifted, and run ([18, 17], 16, 15, 1 .. 14). To connect these, you need to run longer wire jumpers instead of the 2-pin headers. Here is the wiring for the Lumex at right.
Note the two longer wires running across to the other side of the pinout strip.
Another interesting part of that Lumex LCD panel is that the backlight needs 6v to run. The Arduino provides 12v (or input), and with some creative use of the empty button space, we can make a voltage divider and deliver 6.5v. The image below shows in yellow, pink, and tan, three sets of pad triplets that are unused where you can route 12V, divide it, and then jump your 6.5V to the pin 15 pad instead of running the “pink” jumper wire like in the picture at above right.
