Installing Font Awesome on Ionic in 3 steps

1. Install it via npm:

  npm i @fortawesome/fontawesome-free

2. Add this to your main.ts:

  /* Fontawesome */
  import "@fortawesome/fontawesome-free/css/solid.css";
  import "@fortawesome/fontawesome-free/css/regular.css";
  import "@fortawesome/fontawesome-free/css/fontawesome.css";

3. Done!