Select a speed reading program online that uses a method you're most comfortable. Some methods of speed reading are skimming, meta guiding and basic focusing. Programs like Spreeder and Zapreader are the most popular on the market. There are other sites, like MrKent's free speed reading course, that provides methods that you can use on your own without investing money or downloading programs.
Set the reading speed on your selected program and incrementally increase it every week. This will help you to make personal benchmarks. You'll see whether or not you're actually understanding and grasping your chosen method of speed reading.
Use your program and practice 15-30 minutes each day. This helps sharpen your ability to use your chosen method. Speed reading is a skill, and like any skill gained, you must practice to perfect it.
Start with something small. Most often with these online programs you can select what material you want to read. Try not to jump ahead. It is important to comprehend and retain small bits of information first. Oftentimes when presented with a mass amount of information, our minds and eyes are all over the place. Work on your method and then volume.
Only speed read when it is appropriate. Once you get the method down you might want to hurriedly read everything. However important things, like legal documents or even a letter written from a love one, deserve to be read at a reasonable pace so that you fully comprehend what the document is trying to convey.