Add a floating div tool bar that appears on all pages in your apex application and add buttons, items and images... onto the tool bar.
Create new region template as a floating div as shown below
Go to shared components > Templates > create
Then go to page 0 and create a region using newly added floating region template and give it a REGION_STATIC_ID example: floatdiv
Add the below into css stylesheet into your application for id floatdiv as shown below