A friendly URL is useful for pasting into an email or putting on a poster or flyer. It's easy to read and remember (compared to the URLs that are auto-generated by Libguides).
Guide type + group assignment
Guide type = General Purpose (for most guides)
Guide type = Course Guide (if it's for a specific course)
Group = Special Collections
Use General Purpose for now.
If your guide is for a specific course, check to see if Main Library has a course guide, and consider collaborating with the guide author to add your pages to their guide instead of creating separate guides in Special Collections.
Private (while you are working on the page)
Published (when you are ready to go live)
Set the Status to Private as soon as you begin your guide. That way you can share a link to it with your colleagues for feedback during the draft stage.