In order to make any real changes to the game or to create your own Witcher mod, the first thing that must be done is to extract the original files.
- Familiarity with (or lack of fear of) the game directory structure and file formats.
- Ample hard disk space.
All of the data that is used by the game is stored under the \DATA directory. Take a look at it now. You will find a whole slew of files there. Quite a few of the files are unpacked — these are of no interest for now. We are interested in the ones that are packed — the ones with .BIF file extension. The BIF files are containers that "wrap" most of the game data — these are the archives we will want to extract. BIF files alone are useless though, we will need the accompanying KEY files as well, because the BIF files are indexed by KEY files — this mumbo-jumbo is irrelevant for now; if you are interested, read all about it on the KEY BIF V1.1 format page.
At the moment, there are no official tools to extract these files, so we have to rely on third-party applications. These are listed at the bottom of the KEY BIF V1.1 format page, in the external links section. Pick any one of those, and use it to extract any KEY/BIF file you want.
It does not matter which tool you use, you will have to select at least one KEY file that you want to extract. Some tools allow to be more specific, like UnBIF or BIFRip, that allow the extraction of specific BIF files, but in the end you will have to hit an "extract button". Make sure that you extract all files outside of the game directories or they may interfere with the game itself: wasting resources and confusing you with non-working modifications.
The time needed to extract the data depends on how fast your machine is and on the amount of data you plan to extract. I took me a little over seven minutes to extract all data from the game — so do not be surprised.