I looked at, and the best way to do this, would be similar to @vincent sanbox site:
On the vertical dots, I suggest adding a hover over the dots, that creates a flyout of that section with name:
Any other way, if you add 8, 9, 10 sections, an arrow wouldn’t allow the user to know where their desired section is?? With this setup, users can hover over “color-coded” dot navigation, and get a fly with section name; now it’s easy for them to experience the page. Of course, they can use scroll bar as well.
This would be my suggestion is you’re going for sticky side bar navigation. Color code + Flyout Name!
The block down / up arrows is tough to create, because the complicated hide/show and show another block. You would basically have to create many arrows, like 2 for each section. Man, this wouldn’t be fun at all.