The "vanilla" Xfce desktop starts up with two panels: The one on top features an application launcher, virtual desktop browser, and desktop functions (clock, wireless network connections, battery indicator, etc). The bottom panel includes launchers for frequently-used programs (terminal, file manager, web browser, etc) and window buttons for currently-running applications.
Since the top panel included the desktop functions, I figured it was easiest to start from that, and delete the second panel. It's a fairly straightforward series of steps to modify the top panel: right-click on the panel, and select Panel → Panel Preferences. Under the "Items" tab, you can add new functions, modify features, or delete unneeded functions. When done, my "Items" list looks like this:
- Launcher: Chrome
- Launcher: Firefox
- Launcher: File Manager
- Launcher: Terminal
- Window Buttons
- Applications Menu
- Notification Area (external)
- Action Buttons (external)
It's up to you what programs to include in the launchers. These are meant to be your frequently-used programs. In my case, I do a lot of writing and web design, so I often need a terminal, file manager, and web browsers. Add whatever programs you use most.
Each Separator is transparent, and exists only to provide some visual spacing. Under Window Buttons, turn off "Show button labels." The panel itself is set to 38 pixels high, 1 row, 100% length.
To make the Applications Menu look like the Aura desktop applications menu, turn off "Show button title" and change the icon. Xfce provides a suitable "3x3 grid" icon as Action Icons → view-grid-symbolic.
I prefer to use 12-hour "am/pm" time for time, so I set my clock to use "%l:%M%P" as the custom time format. This displays time as "8:49pm" instead of the European-standard "20:49" format. Similarly, I set the tooltip to use a US-standard format by entering "%A, %B %d %Y" as the custom date format. If you hover your mouse over the clock, Xfce will display "Sunday, June 02 2013" ("%e" will produce the day of the month without the leading zero, but inserts a leading space instead, which looks weird; I have opted for the leading zero instead).
Move the panel to the bottom of the screen, and lock it in place. Delete the second panel.
Finally, I changed the color scheme to be more familiar, and to allow the panel to visually fade into the background, I set the Xfce desktop theme. In the Applications Menu, select Settings → Appearance. In the "Style" tab, select "Bluebird," which gives a nice dark grey with white text. This also changes the window borders to a nice blue (inactive windows are greyed out) which I find more pleasant to work with.
Power users may notice that this desktop doesn't include the virtual desktop browser, which allows you to represent different desktops on one system. For example, you might use one virtual desktop just to run your email program, a second virtual desktop for your web browser, another for your programming editor, and a fourth for other tasks. As you might guess, virtual desktops are often used by programmers and other highly-technical users, but I omitted the virtual desktop browser for the sake of simplicity. If I were to re-add virtual desktops to this, I would likely create a separate "panel" on the right edge of the screen that lets me switch between virtual desktops.