i have done some side work with one of the exchanges before, and i will tell you they are getting slammed with requests in general from the many cryptos/icos.

from what i have seen they take a interest in coins that will have a decent market and have decent support.

Only take each of you 10 mins max. Couple things to help: " If you guys really are strong on the success of Credence, take the few mins and help "

1.) https://www.yobit.net/en/addcoin/             -request coin add
2.) https://twitter.com/YobitExchange              -send them a tweet @yobitexchange

3.) https://twitter.com/CoinExchangeio             -send them a tweet @CoinExchangeio

Post on your twitter about credence, make a youtube video, tell your dog, your cat & gold fish

I will be making more vids of credence over the next couple days:

https://www.youtube.com/channel/UCseFeyC9u_RLnyoNzQYv34w  

Crypto Kong will most likely be doing another video

https://www.youtube.com/channel/UCR7XuKH4TKU5FUvvQFx89Kw

Once credence has the site/platform running, its a whole different story. My advice is :  Buy/Hold/Stake