Splendid geomantic omen: what is eight characters and six reds?

Eight characters and six reds refer to Meridian, Ugly No, Shen Yin, You Mao, Chen Xu and Hayes.

For example, a person was born on the 25th day of the twelfth lunar month in 199 1 year (Year of the Sheep). His birth dates are: Xin Wei, Xin Chou, Chen Jia and Jia Xu. The ugly day and the moon in the eight characters do not conflict, but the day and time of the earth conflict with each other.