If you want to make good profit then I would not trade Bitcoin. You need a high stake in order to make little profit. I would rather recommend to speculate on undervalued coins, or even on typical and known pump and dump coins (which are currently in dump mode of course). A good platform for doing this is Yobit or Poloniex. You need little stake to start. But be careful, this strategies could mean the total loss of your investment.
Recently i have also started to trade in Altcoins and really if you do little bit reasearch about coins then you can do trading and earn nice profit and users in yobit are also very friendly , i have been using yobit for last 3 months and trading is also fast. for bitcoin trading we need investment but i yobit you get freecoins with that you can start your trading.
Yeah i am also tried making some profit in yobit fast growth in altcoin and you can easily understand the concept of the site..
But there's many shitcoins in yobit.. so beware to buy shitcoins better to research first and watch the fluctuate of the price of altcoin..
you can't tell which coin is good and which one is bad just by looking at yobit. since that exchanger is not so popular, the trading volumes are so low and in some cases unreal.
a couple of days back i was looking at bitcoin price for example and it was $230 @<0.01 vol while price was $207 everywhere else.