Open the .ino file provided and change the location to the appropriate longitude and latitude (google maps can help). Also take note of the defined parameters you might want to change, namely

• Number of Neopixels in your setup
• The brightness of the LEDs*
• The pin you want to connect to

The RTC used is the the DS3231, which is quite common. Be sure you modify the code if you decide to use a different module

*The brightness of the LEDs can be modified using a potentiometer but that is off by default. Uncomment the right block of code (marked in code) to enable it and note the analog pin used.

Most RTC clocks come with false time, so be sure to update your clock to correct UT time (NOT YOUR LOCAL TIME). You can use this website to find UT time.

As mentioned before, I used DS3231  for this project, if you use any other module please be sure to update the main code accordingly. It's really simple, just replace the (few) RTC function calls in loop () to your RTC's function calls.

It's a great idea to first layout the design on a breadboard to make sure everything works.
To test an entire cycle to can modify the changeColor() function call and feed it a continually changing parameter(a for loop is enough).

If you plan on keeping the MCU with the board (i.e. Arduino UNO) power input should be simple. If you want to use the bare microcontroller (i.e. ATmega328) you'll need to a bit more steps; I found a USB connector to be helpful here.

When you're satisfied with everything, get to soldering!