By living your life one day at a time,you live all the days of your life.
应当活在当下,生活在生命中的每一天.
全文应当是
Don`t let your life slip through your fingers by living in the past or for the future.
不要因为生活在过去的回忆或未来的幻想中,而让你现在的时间从指缝溜走.
By living your life one day at a time,you live ALL the days of your life.
应当活在当下,生活在生命中的每一天.