Editor
For the convenience, Lokalize has toolbars to speed up many operations and, for expert users, there are many keyboard shortcuts. Shortcut keys can costomized using Settings Configure Shortcuts.
By default, the main window contains six parts. The upper-right box is read-only and contains the current msgid (source text) field from the opened PO-file. The edit box just below this contains the msgstr (target text) field related to the msgid shown and here you can input or edit the translated text.
The main default lokalize window
This shows the default window when a file is opened.
The top-left part of the main window shows the Translation Units. Below this, there is Unit Metadata section and it contains comments relevent to the currently displaying source text. In the lower-left, there is Translation Memory section which shows the suggested translations from the translation memory database for the current source text entry. On the lower-right corner of the window, glossary section is shown.
Translation files are opened in separate tab, with two big multi-line edits as well as a bunch of toolviews. These views can be stacked (similar to tabs), shown separately, or hidden. Translation files consist of many English-target pairs called units. A unit typically correspond to a single string in the user interface, or one paragraph in the documentation. The purpose of the first multi-line edit is to display the original part of the pair. The purpose of the second multi-line edit is to display the translation. You can navigate through the units via the Translation Units view or by using Page Down and Page Up
A unit may be translated or untranslated. A translation of a translated unit may be ready or not ready (also called fuzzy sometimes). If the unit is not ready, its translation is rendered in italics. allows you to easily navigate through the file according to the state of their translation. See Go menu for the shortcuts. The status bar at the bottom of the window shows current string number, total number of strings, total untranslated strings, total not ready (fuzzy) strings and status of the current string respectively. When navigating, untranslated units are treated as not ready. Also you may use filtering feature of Translation Units toolview. Pressing Page Down actually takes you to the next unit in filtered/sorted list of that toolview.
To the main window one can add many more sections like Alternate Translations, Primary Sync, Secondary Sync, Binary Units by using Tools Toolviews from the main menu.

Toolbars
You can add or remove actions in the toolbar using Settings Configure Toolbars... from the main menu.
Configure Toolbar
Here you can configure the toolbar.

Shortcut keys
Using shortcut keys during translation, one can save time. To configure shortcut keys, use Settings Configure Shortcuts... from the main menu.
Configure Shortcuts
Here you can configure the shortcut keys.
If you are doing translations for KDE, then either you will already have project file in your languages folder (usually named index.lokalize), or you can select Project Create new project and the wizard will download translation files for your language and will create project for you.
It is recommended that you get used to the keyboard shortcuts instead of the menus and toolbars for increased productivity. For example, use the L to focus Quick search input line to filter unit list in Translation Units view. Once you are done, press Page Down to start moving along the filtered list.
If you are working with translation files in XLIFF format (definitely the case when you translate OpenDocument), then extended states are available (new, needs review, approved, ). You may select them in drop-down menu of Approved button in the toolbar. Classification of the state as ready or not ready depends on the current workflow phase (translation, review, approval). A default phase for you depends on your role in the project (set in project settings). Each unit usually contains information about phase it was changed last time, and for each phase its owner is logged to the file.