Connect the Kindle to your computer using its USB cable. The computer will automatically recognize the Kindle as a mass storage device.
Double-click the Kindle's drive letter or its icon on the desktop to open the Kindle on the computer. Inside are three folders called "Music," "Audible" and "Documents."
Drag and drop your e-books into the Kindle's "Documents" folder, and then disconnect the Kindle once the file transfer is complete. The e-books will be immediately accessible from the Kindle's library.
Press the "Menu" button on the Kindle's keyboard and click "Settings" using the five-way controller. Take note of the Kindle's unique email address displayed on the "Settings" page.
Create a new email on your computer and add the e-book files as an attachment.
Send the email to the Kindle's email address. After a few minutes, the e-books will be automatically pushed to the Kindle and will appear in its library with no further action required on your part.