1.Download font-awesome from here.
2.Copy the font-awesome directory into your project.
3.In the of your html, reference the location to your font-awesome.min.css.
<link rel="stylesheet" href="path/to/bootstrap/css/bootstrap.min.css">
<link rel="stylesheet" href="path/to/font-awesome/css/font-awesome.min.css">
4.In the project start using font like this:
<p><i class="icon-camera-retro icon-large"></i> icon-camera-retro</p>
<p><i class="icon-camera-retro icon-2x"></i> icon-camera-retro</p>
<p><i class="icon-camera-retro icon-3x"></i> icon-camera-retro</p>
<p><i class="icon-camera-retro icon-4x"></i> icon-camera-retro</p>