The best way to get started speed reading is to do warm-ups that allow you to isolate one sentence at a time. A card works well for this. Place a card or a piece of paper on the page, directly under the line you're reading, and move the card down as you quickly scan each sentence. Practice picking out the main words and scanning over conjunctions and other minor words that do not express the main focus of the sentence.
One popular method of speed reading is to place the tips of your fingers just below a line of text and move it smoothly to the right, letting the movement guide your eyes. Using a swift motion without stopping forces your eyes to move across the page and pick up only key words as you go. This method of speed reading, once mastered, is an effective way of reading quickly while maintaining comprehension.
Maintain your progress by taking speed reading tests designed to let you know how many words per minute you read and how much of what you read you were able to comprehend. There is a free speed reading test online to get you started (see resources).