Here are the steps to follow.
- Download the free ibooks application, which allows you to search for free books, purchase new ones, and add all of your pdf to your virtual library.
- Open itunes.
- Drag your desired pdf files into your itunes library.
- Highlight those pdf files to be added. Right click the file and select "get info." Then, select "media type: book."
- Connect your iphone to your computer.
- Plug your iphone into your computer and select "sync books."