You start by making a decision on how much money you will place on the trade. Potential profits are calculated as a percentage of your initial stake, so the more money you put down then the bigger your profit could be.
As an example, imagine we put £20 into a binary trade which promises a 70% return. If we won we’d receive a return of £34, yet had we put £200 down as our stake, we would have seen a return of £340.
Of course, the risk is that by increasing your stake you also increase the amount of money you could lose if the trade proves unsuccessful. With a £20 stake the most we could lose is £20, while if we put down £200 we could lose the whole £200.