Contributing helps gathering files more quickly, and in most cases doesn't require more skills than just playing the game.
Please do not attempt to brute force the names unless you are sure they are original, we are trying to gather original file names, not hash collisions.
Files can be gathered by either guessing the name or playing the game and loading files.
To gather files while playing you can download a Bigfile logger. This will log all files that are being loaded to a text file, you can then submit the contents.
After gathering files you can submit them on the associated project page, the system will then check whether they match and add them to the database.