WAR THUNDER
Install custom camouflages
Installation starts by creating a camouflage template for the selected vehicle in game. War Thunder then creates the correct folder inside UserSkins.
Step-by-step guide
Choose the vehicle
In the hangar, select the tank or aircraft you want to customize.
Open Customization
Open Customization and press Create user skin template. The game creates a template folder for this vehicle.
Open the generated folder
Go to the installed client directory, open UserSkins, then the template folder:
War Thunder\UserSkins\template_ussr_t_34_85_d_5t
Replace the contents
Remove the generated folder contents and extract the downloaded camouflage files there. They may include .dds, .tga and .blk. Keep the archive structure.
Refresh the list
Return to Customization, press the refresh button for user camouflages and select the one you installed.
If it does not appear
Check the exact vehicle variant and template, extract the archive, and make sure files are not inside an extra nested folder. Refresh the list again.
Official source: War Thunder Wiki