Xmodulo published a guide about configuring the Raspberry Pi for the first time

You flashed an SD card with Raspberry Pi image, and plug the SD card into Raspberry Pi. Then what next? The first thing to do after booting Raspberry Pi is to configure your Raspberry Pi. Each Raspberry Pi system comes with its own software configuration tool. For example, use raspi-config for Raspbian, firstboot for Pidora, etc.

In this tutorial, I will explain how to perform initial configurations on Raspbian-powered Raspberry Pi by using raspi-config tool. The first time Raspberry Pi setup includes expanding local file system into the entire SD card space, changing host name, activating SSH service, enabling booting to desktop, etc.

  How to configure Raspberry Pi for the first time