So , news to me Amazon has this great “author page” feature that you can access as an Author (even if you have a publisher), where you can ad a bio, reviews not published on Amazon and so on.
Here is my newly set up one for Amazon Us, there is a Amazon page for each country, so its worth setting them all up.
Here is mine : https://www.amazon.com/author/kathrynrobson
Authorcentral is self explanatory once you get there and a very helpfull tool to track your amazon ranking and compare it to any promotions you have been running.
Hope this helps!