The power supply in these pictures is more amps than in the model I suggested on the previous step. Makes no difference for this tutorial. I don't want you to be surprised.



DO NONE OF THESE STEPS WHEN POWER IS CONNECTED. YOU WON'T GET TO MAKE THAT MISTAKE TWICE.

Cut off the end of the power plug that doesn't go in the wall.

The three wires inside are black, green, and white

The white wire goes to the power supply's neutral (N), the green wire goes to ground, and finally the black wire goes to live (L).

The three wires are brown, blue, and yellow

If you have a cable that is brown/blue/yellow or brown/blue/green: Brown

is Live (L), green/yellow is ground, and blue is neutral (N).

Connect LEDs to power

From there a red wire from the LEDs to V+.

There's two white wires. Connect either one to to V-.

Connect Arduino to power AND LEDs



Connect the other LED white wire to Arduino GND. Look around the board - there's more than one GND and they're all the same. If you have a soldering iron feel free to tin the white wire so it's easier to stick in the Arduino.

Connect a red wire from power supply V+ to Arduino VIN.

Connect a white wire from power supply V- to Arduino GND.

Now the Arduino and the LEDs are getting power from the PS and they have a common ground (white wire/GND).

Keep it together

I put a rubber band around the arduino to hold the wires in place.