Trailing stop-loss is different than a normal stop-loss setting. With normal stop-loss if you set the percentage to 6%, the currency will be sold with a loss if it goes down more than 6%. With trailing stop-loss it will keep track of the price and move the stop-loss rate upwards when the price of the currency goes upwards. So if you set the trailing stop-loss percentage to 1% you will have a stop-loss of minus 1% of the highest rate it reached. So if the currency moves up 10%, the stop loss(sell) will be at 9% profit. With trailing stop you don't lose out when your profit % goes up higher than you expected.
Below you can find how to use it:
Arm trailing stop-loss
If you only want to let the stop-loss trail up when it is going to make a profit, then you should enable arm the trailing stop-loss at a certain percentage. The arm trailing stop-loss setting is for when the trailing stop-loss should start trailing, for example when the price is 2% up.
Use trailing stop-loss only
When selected, the percentage profit setting of the position and your config will be ignored and the position will be sold when the trailing stop-loss is triggered.
Reset stop-loss after failed orders
When enabled this will reset the trailing stop-loss after a trailing stop-loss sell order is cancelled/timed out.
Note: When this is turned on a new trailing stop loss will start after manually cancelling the order.
For more information: