You can add titles and some images to most of labels and titles on site, including menus and tab labels.
To add icons, go to site RH Icons and copy code of icon which you like.
Now, make next code
<i class="rhicon rhi-bolt-regular"></i>
As You see, we added our copied class to class of icon. Then, place whole code in label of item
If you need images, you can copy them from Emodji copy site. Simply copy image as you copy text and place it in label field