The following tools can make your life as a KDE translator a lot easier. Do not worry if you do not understand the feature listings in the respective chapters of this HOWTO on first sight. You will understand them as soon as you know how GUI and doc translation really work.
Apart from just using your favorite editor you have basically the following three options:
KBabel by Matthias Kiefer (full support for Unicode): the recommended program for GUI translation at the moment
and the GNU Emacs PO module (po-mode.el) that comes with the GNU gettext package (Unicode support only with additional packages)
Features and advantages to using these specialized programs are listed in the appropriate section on GUI translation.