You'll read faster and comprehend more if you read in an environment that's comfortable for you. Enjoy relaxing music between studying and exams. Drink plenty of water. Chewing helps feed oxygen to the brain and can help with clear thinking. Prepare for the exams by studying in setting as if you are in the exams. Exam questions and consider much time you have on each question not to stay too long with the tricky ones. A little bit of caffeine stimulates the brain but too much is no good so go easy on the stuff.
These are suggestions do what you feel comfortable doing and modify according to needs.
To read quickly and efficiently, it is absolutely necessary that you are relaxed and focused. The state of mind that we will attempt to introduce you to is the same one that athletes strive for in order to perform their best. This is a zone that will facilitate fast reading, deep learning, and ultimately, a sense of accomplishment.
Getting into a hyper focused and relaxed state isn't as hard as you might think, and simply requires following some very basic steps. As you progress with speed-reading skills, you will be able to pare down the steps and get yourself into this state in a matter of 30 seconds.
In order to succeed at anything it is necessary to remove all self-doubt and to cast aside any inhibitive preconceived notions you might have about the task and your ability. Think of all those negative feelings you have about reading. For example, you might feel that reading is boring, that you have trouble retaining the information you read about, that you take so long to get through a single chapter, and so on. Anyway, mentally rake up all these assumptions you have (as if they were autumn leaves) and picture putting them in a plastic bag. Tie a knot in the bag and fling it off a cliff---watch this bag of junk sail away into nothingness.
Think positively about what you are about to do. Think, "this is great…I am going to learn to focus and to zip through reams of reading material. This is a skill that I can learn and I will learn." You mind have a very large capacity to learn and that you can definitely read quickly and effectively. Imagine how much you are going to learn and how much time you will save with this new skill. Remember that limitations are self-imposed and as soon as you say "I can", well, you probably can! Believe in human brain.
Sit up straight. Posture is very important to speed reading, if you're slouched, your mind will be "lazy" and inattentive.
Then it is important to become physically relaxed. Top athletes often describe feeling loose and relaxed before the best performances of their lives. The same holds for brain activity. To learn and to absorb information properly, being calm, loose, and relaxed is imperative. To get into this super zone, close the eyes and transport yourself to a serene place. Perhaps you are walking through deep woods. Just pick personal paradise and go there mentally. Use free imagination. Breathe deeply through the nose, from your lower abdomen (this is real deep breathing, using your entire diaphragm, and not just the top part). Perhaps you are lying in the grass on your parent's back lawn, face turned to the sun. Perhaps you are sitting at the edge of a calm lake, toes dipped into the warm water. Breathe in and count 3 long seconds, breathe out and count 3 long seconds. Do this ten times. Soon you will be able to condense this process and get into the mode by taking a few deep breaths.