You will need:
-4 220 ohm resistors
-1 2.2k ohm resistor
Step 1: Add a Button
Connect the button by adding a resistor to ground and connecting the button to power.
Step 2: Add Four LEDs
(Or as many LEDs as you would like.)
Attach the LEDs to the breadboard.
Connect 220 ohm resistors to the positive ends of the LEDs (the long ends).
Step 3: Connect the LEDs to the Arduino
Connect the shorter ends of the LEDs to ground. Connect the resistors to pins on the Arduino (I used pins 13-10).
Step 4: Finish Connections + Add Code
Connect the power rail to 5v and the ground rail to the GND pin on the Arduino.
-Connect the button to pin 2 on the Arduino.
Add your code to the Arduino IDE.