RGB RING How to blink

hello.I have an arduino nano and adafruit neopixel (24 led) ring and I do not know how to blink it every 1 second (for example)
I saw a lot of examples ,I have found many combinations ,I tried to blink it ,but nothing happens...
This is my last example (is like the ring loading) :

#include <Adafruit_NeoPixel.h>
#ifdef __AVR__
 #include <avr/power.h>
#endif

#define PIN  6 

#define NUMPIXELS 24 // Popular NeoPixel ring size

Adafruit_NeoPixel pixels(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);

#define DELAYVAL 100 // Time (in milliseconds) to pause between pixels

void setup() {
#if defined(__AVR_ATtiny85__) && (F_CPU == 16000000)
  clock_prescale_set(clock_div_1);
#endif

  pixels.begin(); 
}

void loop() {
  //pixels.clear(); // Set all pixel colors to 'off'

  // The first NeoPixel in a strand is #0, second is 1, all the way up
  // to the count of pixels minus one.
  for(int i=0; i<=NUMPIXELS; i+=NUMPIXELS) { // For each pixel...

    // pixels.Color() takes RGB values, from 0,0,0 up to 255,255,255
    // Here we're using a moderately bright green color:
    pixels.setPixelColor(i, pixels.Color(180, 20, 0));

    pixels.show();   // Send the updated pixel colors to the hardware.

    delay(DELAYVAL); // Pause before next pass through loop
  }
  delay(1);
    for(int i=0; i<=NUMPIXELS; i++) { // For each pixel...

    // pixels.Color() takes RGB values, from 0,0,0 up to 255,255,255
    // Here we're using a moderately bright green color:
    pixels.setPixelColor(i, pixels.Color(0, 0, 0));

    pixels.show();   // Send the updated pixel colors to the hardware.

    delay(DELAYVAL); // Pause before next pass through loop
  }
    delay(1);

}

Any advices would help me

arduiNICK:

  for(int i=0; i<=NUMPIXELS; i+=NUMPIXELS) { // For each pixel...

This is wrong. First of all, the pixels are zero-indexed. So the highest pixel number is NUMPIXELS - 1, just as it says in the comment in your own code. Speaking of comments, the "For each pixel" is also wrong. You are incrementing i by NUMPIXELS, which means that only pixel 0 will be affected by this code. If you truly wanted "For each pixel", then you need to increment the pixel by 1. You should really get the File > Examples > Adafruit NeoPixel > simple sketch running and make sure you completely understand it before you start messing with your own code.

arduiNICK:

    delay(1);

What do you think these are accomplishing?