The Chinese Almanac - once available in every traditional Chinese home is now hardly visible in the home. This reference book is sort of a go-to source before the family embarks on a major activity such as a wedding, an engagement, house-moving, shop-opening, making a trip, prayer-altar cleaning, even going for a haircut.
For non-believers, this could be pure superstition but for those who believe, the Chinese community primarily, this is a way of life, part of Feng Shui as practised by the Chinese for thousands of years. A culture, if you will.
It is believed that executing something on an auspicious day can mean reaping positive results while doing something major on an inauspicious day can mean disaster as a consequence.
I came across Lilian Too's calendar of Good Days to Wed in 2013. They at WOFS (World of Feng Shui) have investigated the Tung Shu/Tung Sheng (Chinese Almanac) to identify the most auspicious days to get married, as well as unfavourable days which must to be avoided at all costs.
Below is sample for July. You can view the rest of the pre-calculated auspicious wedding days of the year on to Good Days To Wed on the WOFS website.