1. Upload the 'Fonts' folder and the CSS file to your website's root directory.
2. Link the CSS file in the `<head>` section of your website: <head> ... <link rel="stylesheet" type="text/css" href="yourdomain.com/css/flaticon.css"> ... </head>
3. Add the corresponding icon class to the element where you want to display the icon, for example: <i class="flaticon-airplane49"></i> or <span class="flaticon-airplane49"></span>.