1. You will need Chrome driver executable on your system. So download it from (
http://www.seleniumhq.org/download/) unzip it somewere in your system. I will assume you will place it to C:\chromedriver.exe
2. Then you have to set it up in the system properties. Here is the Java code pasted from my Selenium project:
File file = new File("C:/chromedriver.exe");
System.setProperty("webdriver.chrome.driver", file.getAbsolutePath());
WebDriver driver = new ChromeDriver();
Basically, you have to set this property before you initialize driver
Hope that helps