The Plasma FAQ Configuration page tells you where to find new themes for your Plasma Desktop, and how to install them.
The first thing to look at issection - there you can select .
You can also use the QtCurve to make GTK apps use the current Qt/KDE style. Instructions on how to install and use it for Kubuntu (you just get rid of apt-get specifics and use GUI package manager of your distribution instead of Ubuntu command line) can be found here. Please refer to your distribution for packages.
Since Qt 4.5 release, there is support for gtk themes for Qt GUI styles. In most distributions this will be available from KDE software version 4.3.
Some applications (Qt4 applications) running under KDE4 do not share the same color scheme as KDE4 applications, have an odd background color, or have white text on white buttons, etc. If you change the palette/color scheme in, the Qt applications you have running become the correct color, but change back once they are restarted.
Solution You may have a leftover .kde folder from KDE3 in your home directory, and Qt looks at it first instead of the .kde4 settings folder. You can either rename or remove the .kde/share/config/kdeglobals file, which will cause Qt to use the .kde4/share/config/kdeglobals file instead. The next time a KDE3 application is started, it will regenerate the .kde/share/config/kdeglobals file, and will use the default KDE3 theme and colors, but will not affect the Qt applications colors.
Open, and select , and take a look on the tab. Here you can customise the buttons in the title bar. '?', '_' and the square represent the What's this?, minimise, and maximise buttons. 'H' is a spacer. One or more can be added as desired. Your version may also have a circle - this is the ring of a radio button, the setting for showing windows in all desktops.
You can re-arrange them as you prefer. Left-handed people, for instance, may prefer to align the controls from the left, instead of from the right.
The use of Desktop Effects is controlled by KWin. You can see more information about them on the KWin page.
Install compiz. Open System Settings, choose themodule in the tab, choose in the Window Manager combobox and restart your desktop.