1. ) Adding transparency to windows
This step is the easiest. All you need to do is to go to Settings->Window Manager Tweaks->compositor
There you gonna find plenty options to set and add some transparency to windows
2. ) Setting your top bar (aka panel)
This is about making the top bar ,or also make it a bottom bar (like MS windows), to look good.
Go to settings->panel // From this menu you can delete panels or make 1, or more
(optional)To move it to the bottom of the screen uncheck Lock Panel and grab the panel from its handles (they are on the left corner of it) and move it to the bottom.
Now you will notice that the panel section contain Three Tabs. Display/Appearance/Items.
The first tab is about choosing panel's position and size. Appearance is where you make your panel transparent and using a theme setting if the theme you are going to use supports some configuration to panels. Leave Style to none if you are going to use a theme. Tweak the Alpha to get the level of transparency you want.
The third tab called Items is about adding plugins to your panel or remove em. The most notable plugin I'd like to talk about is the Applications menu plugin. Press the preferences icon on this plugin.
I want to describe especially this plugin because it has the awesome feature to add your custom Icon for the "start menu button" and its name also. For this example I used the logo of my linux distro and the name start. You can always remove this plugin like a boss. Please be careful with the icon, it needs to be saved somewhere, wherever you want, but not delete it. If you delete the icon then the default xfce icon will be used.
3.) Adding a theme
If you were wondering why my windows have this gray colour and these icons then all of these are themes. That's a great feature of xfce. There's a vast of themes all free in this site xfce-look also on devianart.
For this tutorial I will use xfce-look.org. See the navigation panel of the site. For the purpose of not making this tutorial an advertisement of themes (even if they are free I won't suggest any theme, I will just explain how to get em work)
Select themes, then select XFCE. The pure xfce themes I prefer em because they keep things clean. They just need to be extracted and copied to the /usr/share/themes folder they don't need you to install custom engines or anything else. So select a theme then download it and extract it, then copy the folder itself of the theme to /usr/share/themes.
Now to make the theme work you need to go to 2 different sections and select the theme you installed. Themes can contain a theme that changes the style of windows bar and its icons (icons such as the X symbol you press to close, the square for maximizing window) and also your windows color scheme. If you successfully extract the theme you should get your themes showing in these 2 sections :
first to settings->appearance
second to settings->window manager
Note that a theme may not contain both settings for windows color scheme and bars/icons.
Select your themes and enjoy.
4. ) Changing system Icons.
Last but not least you can select your own Icons for folders for example, control panel icons etc. This time in the xfce-look site select icons for its navigation panel.
Select the icons you like. Download,extract and copy the folder to /usr/share/icons . Then go to settings->appearance->Icons. Select em. Enjoy !
5. ) Adding a startup dock
This step is quite optional but I felt like to add it because it makes the desktop very pretty.
One of the best docks out there is docky. Most linux distros have it on their repositories.
So install docky or cairo-dock another dock. I prefer docky because it happened to me to be less buggy. After installing docky things are pretty obvious. Select the anchor icon from it to customize it, the settings are pretty easy. Run a program go then to docky right click it and select to pin it so you make a shortcut of it.