A major advantage of trading futures is the fact that you have an extreme amount of leverage. A good way to consider the risk is to think about the following. The E-mini SP futures (ES) is currently trading around 1290. It is $50/point which means the total contract value is 1290 * 50 =$64,500. Buying or Shorting 1 ES future would be the equivalent of buying or selling $64,500 worth of the SPY. On an average day, the ES moves about 15-20 points which means if you were to buy the high and sell the low you would lose on average $1000 per contract (hopefully that would not be the case). If you are not comfortable with that you could look at trading a lower valued contract like the NQ which is around 2280 at $20/point which means it is valued at $45,600. Most futures brokers will allow you to trade eminis for $1000 or less intra day. The risks you hear about with futures is because of the leverage they provide. Leverage is great when it goes in your favor but bad when the trade goes against you. If you have traded stocks a good bit you will appreciate futures in the leverage that they provide. I would say if you decide to trade futures maybe start out with the NQ or the YM as opposed to something like the Russell because while the Russell is a great instrument to trade once you know what you are doing, it is very volatile.
