Veriael Especially what to put into extension fields...
Once you have the link extension installed, you will find a section links
in the administration. Her you can manage your links (add, edit, delete). Adding a link just needs a title and URL. Furthermore you can mark, if it's an internal link and whether it should be opened in a new window.
The generated dom node for your links looks like:
<li class="item-link1">
<a class="LinksButton Button Button--link" target="" href="..." title="...">...</a>
</li>
The second link will have the class item-link2
and so on.
You can easily apply CSS rules to that link e.g.
.item-link1::before {
font-family: FontAwesome;
content: ...
font-size: ...
}
Hope this helps.