I am personally limiting myself to 8% per trade at the moment, but I have risked less and much more... I do not like to say this because I have not implemented it myself, but... I would encourage anyone who has not done it to ask themselves if it were possible to give a trading percentage (i.e. percentage of their equity/capital) to represent the measure of confidence in a particular trade; for example: 1%-2% = low confidence or expectation of a particular trade working out in our favour; 3%-4% = low-to-medium confidence or expectation (etc.); 5%-6% = medium confidence or expectation (etc.); 7%-8% = medium-to-high confidence or expectation (etc.); 9%-10%= high confidence or expectation (etc.). How easy or not it may be to quantify one's confidence, well, that is indeed a grey area...