You cannot directly drive 12V LEDs from a Arduino. I used 2 ULN2003 ICs I wired up the Arduino to pseudo random blink the Baomain 16mm push button momentary switches. 

Here is a good representation of the circuit in GIF format. You do not need a resistor before the LEDs as they have one built in. I then heavily modified the "A clean sweep" program credit to Adafruit. Mostly adding additional LED channels and randomness in the timings. Here is a link to their awesome tutorial for Arduino multitasking. (Link)