There is no way to salvage the situation, if you were going long and then the price goes down in a dramatic way and you did not had a stop loss ready then you will lose a lot of money, it is that simple, which is why you must use a stop loss at all times precisely to avoid this scenario.
However now that you are immersed on this scenario your only chance of success is for your strategy to be a good one and for it to allow you to eventually recover the money you have lost, an unlikely possibility as if your strategy was that good then you would not have lost so much money already in such a way.
Salvage can also mean to end the situation. There must be action that can end our trade and one of it is like others are saying and that is to "short sell". Often times we are being recommended to use a stop loss but there are professional traders who didn't use it. Maybe the @OP thinks he is one of them already, and that is why he didn't use the said feature.
Aside from losing less, he could also profit more if the strategy that he is using is a good one. If not then it's fine. We all know how hard it was to create a perfect/profitable strategy in trading. We can always learn from the others or from the experts if we think we can not grow/improve in our own.
experience is actually the best to learn the tricks in trading. combined with continuous reading about this market and equipping yourself with various analyses, in time, you will be more comfortable in executing your trade.