• GCFScape[nemstools.github.io] to extract the csgo game files
  
• CSGO SDK to repackage the game files
  
• Around 30gb free space to extract the game files and repackage them with your modified textures, keeping backups of the original .vpk files unless you want to redownload them.
  
• A cheap sticker placed on the guns you want to preview (you can preview holo and foil stickers on normal stickers)
  
• Patience because the process of extracting and repackaging can take a minimum of 20 minutes to perform

1. Open GCFScape and navigate to your csgo directory



2. Open "pak01_dir.vpk"


3. Extract it to a separate, empty folder.


4. Rename the extracted folder "root" to "pak01_dir"

1. Place your textures into the extracted folders
(extracted_folder\pak01_dir\materials\models\weapons\customization\stickers\stickername)


2. Make sure your sticker .VMT files reference the correct path which is
"$basetexture models\weapons\customization\stickers\foldername\stickername"
Don't forget to do this for your holo and foil .VMT files too

3. Go to "Program Files\SteamLibrary\steamapps\common\Counter-Strike Global Offensive\bin"
and type in cmd in the top bar to open the command prompt.
(You need to have the csgo SDK installed in the same place you have csgo installed)


4. Type vpk.exe -M and the path to your extracted pak01_dir folder


5. Wait until it is finished, DO NOT CLOSE CMD
You know it is finished after it allows you to type in commands again.

6. Drag and drop all of the new .vpk files into the csgo game directory. If it gives you errors, make sure you have csgo and the csgo sdk closed.
You cannot play csgo while you have your replaced textures, to be able to play again, delete all .vpk files and validate your game files, or replace with your backup

Change items_game.txt (found at "Program Files\SteamLibrary\steamapps\common\Counter-Strike Global Offensive\csgo\scripts\items") to reference your sticker instead

Find the name of your applied sticker using control+f, and replace the sticker material to the path of your sticker

• If your viewmodel is in left handed mode when you exit the game, the sticker will be flipped. To fix this, type "cl_righthand 1" into the console and restart your game
  
  
• Its pretty inefficient and you have to reinstall around 10gb of files if you do not restore them