As with any currency trading, you can also buy and sell Bitcoin through a broker. One of the Bitcoin exchange service providers is Luno.
 The way it works is very simple, much like a money changer. The difference is that the currency we buy is Bitcoin and the purchase is done online. We can find people who want to buy Bitcoin on the buying and selling platform.
There is a way to buy bitcoin.  
Buy Bitcoin instantly with the instant method.
Buy Bitcoin from the exchange and make trading.
Buy Bitcoin from the community

Good luck...