How can I use Google’s Roboto font on a website?

Question

You don’t really need to do any of this.

Go to Google’s Web Fonts page
search for Roboto in the search box at the top right
Select the variants of the font you want to use
click ‘Select This Font’ at the top and choose the weights and character sets you need.

The page will give you a <link> element to include in your pages, and a list of sample font-family rules to use in your CSS.

Using Google’s fonts this way guarantees availability, and reduces bandwidth to your own server.