You should not have any remains after you do something. But this does not mean to forget all about it. In order not to leave any traces, when you do something, you should do it with your whole body and mind; you should be concentrated on what you do. You should do it completely, like a good bonfire. You should not be a smoky fire. You should burn yourself completely. If you do not burn yourself completely, a trace of yourself will be left in what you do.