How do i swap/replace/change DDS Textures? Thread

Just as the topic says. I'm playing "The Thing" currently and I wanted to Change the Player Model/Textures to one of the (Opinionated.) better looking enemy NPC Models/Textures. I know where the textures/files are, they're all (As known.) DDS Files. But I don't want to screw this up whatsoever, is there anyone who's familiarized with this or has done this before or something similar?

First backup original files in case of that`s yours screws ..than just copy other prepared .dds textures in that folder with paste, and replace original, with same name. That`s the easy part, ..hardest part is to first create those textures with appropriate photo editor and save them with special .dds extension, not just to rename extension, file must be originally exported dds with graphic program.
Sure thing, if game support mods, than all textures coming in folder named mods, and that's the beauty of your work.