Forex day trading - How do you decide the stop loss?

Forex day trading - How do you decide the stop loss?The importance of a stop loss when placing a trade, is very evident. One will not want the entire account balance to come to zero which can happen if stop loss is not in place.But how do you decide a stop loss? Should it be anything?? Are there any factors that decide the stop loss?There absolutely are the factors -1. Foremost is how much can