You begin with a preview, in other words, you skim the table of contents, headings, subheadings, graphs and pictures to get an idea of how the material is organized and what it is about.
Next, you come up with questions about the text. Look at the headings and decide what information you want to know.
The next step is to read the text with your questions in mind. Did you get the answers?
Reflect on what you just read. How is the new information related to what you already know? Think of the ways to test and apply your new knowledge. What kinds of problems could you solve with this information?
Next, put away the text and recite the main points, talk out loud about the material, try to use your own words to explain things and at the same time, incorporate new terms and definitions.
The final step is to review. Summarize the main points and test your comprehension with more questions and hypotheticals.
The PQ4R method is not a quick trick, but the benefit may be well worth the invested time.