poloniex.com
bittrex.com
c-cex.com
yobit.net
Tips: don't buy when price is pumping and don't sell being panic when price gets like 10-20% down within a day time. And also don't follow what chat box suggest you, in altcoin world fud/hype plays important role in manipulating market stay careful.
This suggestion would be the best to consider and i totally agree with him, dont follow on the hypes and speculation especially on the troll box because if you follow them for sure you would lost some of your investments because they are just promoting their coins which doesnt have any guarantee to pump.
I also like these points, but sometime in chat box, some suggestion useful, i am not saying that all are saying right in chat box, but sometime it will be true.
And also if you have skills to do trading than you will be succeed, i saw majority of the persons who have no patience and become panic and sell their all coins in frustration and later on they realize that they have lose.