CFD trading bears striking similarities to traditional shares dealing, but it gives you much more flexibility, as you can profit both from rising and falling markets.
So, if you think that the asset is likely to rise in price, you would decide to buy it, as you can sell it later at a higher price and the difference would be paid out to you. If, on the other hand, you think the market is going to fall, then you sell, to buy it later back at lower price. Again, the difference between the opening and the closing price would constitute your profit.
If, however, the market goes the opposite direction than you anticipated, the difference between the opening and the closing price will be your loss.