How do you get Mario in gmod

Where x is anything that has been created by someone for gmod:

Go to http://www.garrysmod.org/downloads/ and search x; then, find an appealing result; then, download it; if the folder of the downloads contains info.txt, find the addons folder for gmod and put the folder you downloaded into the folder you found; otherwise, follow the instructions that should be somewhere in the downloaded folder; if there are no instructions in the downloaded folder, you're screwed as far as I know.