even counting script help

Using Arduino Project Guidance
2

You should check the interrupt - http://arduino.cc/en/Reference/AttachInterrupt -

a simple example with the built in LED as light

int pin = 13;
volatile int counter = 0;

void setup()
{
  pinMode(pin, OUTPUT);
  attachInterrupt(0, irq, FALLING);  // HIGH -> LOW
}

void loop()
{
  if (counter == 4)
  { 
    digitalWrite(pin, HIGH);
  }
  if (counter >10)
  { 
    digitalWrite(pin, LOW);
    counter = 0;
  }
}

void blink()
{
  counter++;
}