Leverage is there just to increase the size of your opened position. With leverage 1x you invest let's say 1 BTC and open long or short position worth 1 BTC, with leverage 2x you invest 1 BTC and borrow 1 BTC from btc.sx to open long or short position worth 2 BTC, etc. Higher the leverage, the more money you borrow from btc.sx and thus increase the risk. With leverage 10x price needs to move only 10% against you (bet on price going up but instead it goes down) and you'll end up wipped out but if you guessed price movement correctly then you'll double your investement when price goes up only 10%.