Look for the leverage, spreads, margin, and trade size that the broker offers. Also, check whether they offer the kind of asset you want to trade and the different kinds of accounts. Quick order execution is also an important aspect. Commissions, customer service, trading platforms, and tools are other things you will have to examine of a broker, before finalizing on one (or two). As a self-made rule, I always operate accounts with at least 2 brokers. Currently, the two I am using are Turnkey forex and Oanda. And both are stellar!