Datasheet

Solder all the pins of the header with plenty of
solder.
Next we'll place the two LEDs. The first LED is
the green-colored one. This will tell us when the
Arduino and shields are powered.
LED's are directional which means you need
to place it in the right way or it wont work!
Check the LED to find the longer pin. This is the
positive lead. That lead goes into the hole
closest to the silkscreen '+'
In the image to the left, the longer lead is to the
left.
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