How to install : 

1) Download the skin + bus mod
2) Copy the files you downloaded.
3) Go to the Documents folder and look for the Euro Truck Simulator  2 game folder.
4) Open the game folder you found in Documents. You will find a folder named Mod. Enter that folder and paste the files you copied
5) Once done, open the game and enter it.
6) Once you’re in the game, click on the Mod feature, then activate the bus mod followed by the skin mod

Credits:
MTC / HMZ