I can extract/edit textures, but how do i save/test it ingame?

[Cheesecurls]

hey guys, this is my first post here, so please tell me if im posting in the wrong sub.

ive got the .VFS extractor working fine, im well oriented with the DDS format, which seems to be the main form of texture files in .VFS however my question is how would i get the finished texture edits ingame; test them out etc.

i feel there's something simple im missing..

if anyone could help me out, that would be great!