Go to https://etherdelta.com/
Click KNC.
Click other.
Type addres " Contract Address " name "SYMBOL TOKEN" decimal "nbr" click Go.
Click select account.
Click import account.
Type address "your wallet address", private key "your private key", and then click import account.
Make sure your wallet is successfully imported, and have some ETH balances.
If your wallet have TOKEN balances, the amount will be visible in the wallet, in order to be sold on the market, make a deposit by typing the amount of TOKEN, then click deposit.
After successfully making a deposit, your TOKEN balances will move from wallet to etherdelta, then you can trade in the market. Good luck.
Caution: In my opinion all the exchange can not be trusted completely, so do not keep a lot of ETH in the wallet for trading.
Look at this Graphics Guide practice for some token name eBTC
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