Yes, I found it confusing and, as it happens, only worked it out today.
You've found the bit where you can edit bookmarks I assume (the book icon and the hit edit). The key concept to understand here is a setting on folders created in your bookmarks collection. Here's what I suggest.
Open the bookmarks pane, hit Edit, and create a new folder called something like "Toolbar". When you create this you will see that there is an on/off slider setting called "Bookmarks Bar". That's the unintuitive bit. If you set that to on then what it does is nominate that folder as the one whose contents are shown on the onscreen bookmarks toolbar. You now have an empty bookmarks bar and if you want to populate it with your most used bookmarks then you can create or move the bookmarks that you want into this folder and they will appear in the onscreen toolbar.
Hopefully that's clear but if not let me know and I'll have another go.
- Julian