Xfce Show archive.org snapshot gives you a million options to configure your panels. Together with Xfce's sometimes arcane configuration UI, this can be a huge time waster and super-annoying if you need to get work done the same day.
This card describes how to setup a classic panel layout as you might be used to from Gnome 2 or Windows (see screenshot below). You can use this to quickly get productive in Xfce, and as a starting point for further customization.
%d.%m. %R
Have fun with Xfce!