if its the common 100prr-6 (6 terminals on the back):
the A and B termianls are transistors to ground and are used.
Ground is ground (0V) termial
Black and brown to the A and B terminals (reverse if the rotation direction is backward)
5V from raduino 5V reg to the leds (Vcc terminal)
One note I used V4.3 code with my mods and it worked well. Some codes for the
Raduino are slow and if you rotate the encoder quickly it will not keep up.