I think its practice and depends upon what you are reading, we read interesting and easy things so fast but struggle reading some complicated legal/tech document. So may be practice more the subject you want to read fast.
The best way to increase you reading speed is to force your eyes movement to read more characters at once. If you pay attention to your eyes movement while reading, it is not a continuous motion. You eyes are stooping from time to time. The duration of the stop is the same for almost all readers. What differentiate fast & slow reader is the number of character you check during each stop.
Article about the topic: https://tim.blog/2009/07/30/spee...
Practice. Start reading 10 pages a day or 5 and gradually you'll see that you can read faster. what actually happens is that our brain related the visual and the sound of the pronunciation. So after your vocabulary increases, your brain will read faster.
There are some program to train your mind to read from 200-1000 words per second. However, you can train your eyes by reading every day. Start with you familiar topic and increase your speed.
After 10 years, I can skim 300 pages less than 10 minutes.
Notice: Speed Read is about identify key words and understanding the high level structure of content. At least, what you can do is writing a summary of 1-3 sentences.
@divyamundhra I would correct that it's per minute to make it less daunting.
The point here is that you train your mind to read words as an image. It does not matter how many words in front of you -- just an image. Neither read out loud or read in mind will slow you down.