A great way to "read into" a text is to analyze the style, voice, theme(s), setting, type of narration, metaphors used, etc., to interpret how the author was trying to achieve a particular goal. Plenty of professional literary critics have produced material that includes an evaluation of literary devices, but this is probably the easiest way for a novice literary critic (a high school or college student, for instance) to analyze a piece of literature effectively.
Another way classic literature can be brought to life is by reading the novel in the context of the time period in which it was written or the era when the events in the novel took place. Critics may also consider how the author's own life influenced his or her writing. To apply modern principles and concepts to a piece of literature from hundreds of years ago is foolish, as times and perceptions of the world and people have changed drastically over the years. Investigating the "zeitgeist," or "spirit of the times," from which a piece of literature sprung can also help illuminate other text from the same time period, such as the Victorian, Romance or Elizabethan.
A trend in recent times has been to read a piece of literature--particularly a classic written in a time when women were not viewed as equal to men--through a "feminist" lens. In this type of criticism, the critic analyzes how women are portrayed, spoken about or described in a piece of literature. Do the female characters have a voice? Are they important figures who accomplish important things? How do men relate to the female characters? Is the author male or female? All of these questions are pertinent in feminist literary criticism, and they help provide a picture of how the depiction and perception of women has changed over time.