I personally started trading recently, I would suggest that you trade on exchanges that have been hacked before and are still standing reason being that they take their security a little serious eventhough as a trader it isn't advisable to leave funds in exchanges, secondly trade on exchanges with near mid to large volumes, thirdly exchanges that allow you consider "LIMIT AND STOP LIMIT ORDERS on loses and profits" on either buys or sells. These are truely best for traders. Bitfiniex, poloniex, binance etc. Are some I use.