Download the iBook e-book program on iPhone and make sure that iTunes is installed on your computer.

Start iTunes, go to preferences, and see if the Book option is selected in preferences.

IPhone, iPad or iPod? Touch connects the computer with a data cable, and checks the book classification on the left side of iTunes. If there is no such classification, restart iTunes and repeat the steps checked above.

Drag an e-book in PDF or ePub format to this blank area, and iTunes will automatically load the e-book. When finished, you can see the following interface.

Select the device connected on the left (iPhone, iPad or iPod? Touch), select "Books" on the right side of iTunes, check "Synchronize Books", continue to select the e-books you want to synchronize, or select all of them.

Finally, click the application in the lower right corner of iTunes and wait for iTunes synchronization to complete.

Go back to iPhone, open iBook, find and read the e-book you just imported.