It is enough to tell you, that as some of my worst comrades, who are out of the way of doing me harm (having gone out of the world by the steps and the string, as I often expected to go), knew me by the name of Moll Flanders, so you may give me leave to speak of myself under that name till I dare own who I have been, as well as who I am." What does the phrase by the steps and the string mean in the context of this sentence?