Space between link and icon, fontawesome

I would use the .fa-fw class. For example: <i class="fa fa-cog fa-fw"> This adds a visual space (that won't get stripped out) and it's consistent, so when/if the elements stack it looks a lot better.

Instructions: https://fontawesome.com/how-to-use/on-the-web/styling/fixed-width-icons

Don't know if is the best but you can add some margin-right to the i element:

i {
  margin-right: 10px;
}

<link href="//maxcdn.bootstrapcdn.com/font-awesome/4.2.0/css/font-awesome.min.css" rel="stylesheet">
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