If you are new to crypto trading, and looking for a platform to trade, here are some platforms I use.
Share with all of you

1.
Binance : Most recommended. stable, safe, liquidity, commission fee cheap

2.
Bitfinex : Stable, not many coins available
Here is some Korea Exchanges, selling price relatively higher, recommend to sell them here.3.
Bithumb (ps:security issue happened, consider well) 4.
Upbit : Not much volume as Bithumb but no problems so far
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5.
Bittrex - Recommended by FlamingFingers : 2 years exp. and No issue ever
Welcome to other suggestion 
At this point i don't think we have any suggestions to add in the list because i my self really recommend binance and bittrex for those who are day traders, and also security in times of funds protection.