To break it down simply, you need two things: A folder with all the icon files for your taskbar apps. The file has to be in ICO, EXE, DLL, or ICL format. Move all the taskbar app shortcuts to the ...

You can set a dark or any icon of your choice – but the images have to me in the .ico format. Read: How to change File and Folder Icons. As an example, let us change the icon to a dark one.