For your coin to be eligible for listing, Coinmarketcap has provided an information on their listing requirements^[1] and the methodology^[2] they use that can be found on their website.

[1] https://support.coinmarketcap.com/hc/en-us/articles/360043659351-Listings-Criteria
[2] https://support.coinmarketcap.com/hc/en-us/sections/360008888252-Metric-Methodologies

---

The problem with CMC is that I'm often hearing rumors about their bias listing, which leads to people switching to other cryptocurrency ticker sites such as Coingecko or LiveCoinWatch. I am not sure though, that is just my first impression about CMC when people are talking about it back in the days.