I will add this, start depends on weather you want a instant or a wait for movement of SL, trail step can be any number, because trail stop will affect how far behind price your SL stays, (until hit), so if you have a start of 100, step of 50, stop of 25, nothing will happen until 100, then stop will move to 25 behind 100, and every 50 going forward, the stop will move 25 behind price.