Get a short piece of text and lay it flat in front of you. Point your finger underneath each word as you read it. Once you have this activity to where you can keep your eyes and finger on the same word, try increasing your speed. Move your finger faster from word to word and try to keep your eyes at the pace of your finger. Gradually increase the speed until you just cannot go any faster or until you start losing the ability to comprehend what you are reading.
Often you may look back over what you have just read. To help you break that habit get a sheet of paper and use it to cover up the previous text so that all that is left to read is what you have not read yet. This will help you to train your eyes to focus immediately on the next word in the text instead of glancing back over previous portions. This will of course increase your speed in reading.
Using a sweeping motion with your finger, go down the center of the text. This will teach your eyes to take in bigger sections of text. It will also help to widen the span of your eye. Continue increasing the size and speeding up the sweep until you can comfortably cover a small chunk of text in one sweep.
This technique will break your eyes of the habit of reading word for word in order; instead, your eyes will read whatever word they are looking at without moving only from left to right. Run your finger in a zigzag pattern over the text and allow your eyes to follow and read each word as your finger points to it. This is also a good way to improve your eyes' tracking ability.