Numerology: The number 8 (八, bā) is considered extremely 吉利 because it sounds like 发 (fā), as in 发财 (fācái, to get rich). The number 6 (六, liù) is also 吉利 as it sounds like 溜 (liū, smooth). Conversely, 4 (四, sì) is highly unlucky because it sounds like 死 (sǐ, death).
Colors: Red (红色, hóngsè) is the ultimate 吉利 color, symbolizing joy, fortune, and celebration. It's used for weddings, festivals, and the famous red envelopes (红包, hóngbāo).
Events: Choosing a 吉利 date and time for a wedding, a business opening, or even signing a contract is a common practice, sometimes involving consultation with a fortune teller or the Chinese almanac.