Make sure they are regulated and ideally in your country.
There is talk of lots of toxic money since the Swiss announcement so be careful their operation was not affected.
Most of the big brokers are not scams, they provide a good service to allow us retail traders to mix it with the big boys.
The scam is the fact most traders lose and a lot of brokers make money from those losers. They tend not to actively tell you that you will be one of the 95 percenters who lose and we will profit from you.
Understand how your broker operates, check their regulations, deposit small and increase once you trust them and you should be fine!
What about for the future? Should we select STP or market makers to have negative balance protection. As i have understood we should now focus on market makers which have not affected. How to you choose a good market maker if any exists? Is it only regulators you need to watch ?