Be sure to add as many links as possible to any helpful blog posts, websites, tools, and resources that could be useful to the process.
If it's something that wasn't created by you be sure to give credit where credit is due and get permission (not just for the commercial use of someone else's property, but because often times, the creator of the resource will also be more than happy to promote your guide if it features their stuff in some way - more on that in the promotion guide I mentioned earlier).
Adding a URL or hyperlink to a specific word(s) or link is much the same as adding an image or video.
Select the text you want to hyperlink by clicking and dragging over the entire section with your mouse, then click the "Link" button from the far right of the guide editor to pull up the hyperlink menu.