How do you install add-ons to Garry's mod?

Answer 1

Addons are quite simple to install into Gmod 10/11:

-Firstly you need a properly structured addon (should be a folder containing other folders and a text file called "info.txt". The text inside "info.txt" should also be structured properly. As long as the maker of the addon has done this, all you need to do is copy the folder to:

%SteamDirectory%\steamapps\%SteamUsername%\garrysmod\garrysmod\addons

To clear things up:

-%SteamDirectory% means the folder that steam is installed to. This is usually something like "C:\Program Files\Steam".

-%SteamUsername% is your steam user name (the name you use to log into steam)

-There are two "garrysmod" folders there for a reason, i havent just made a mistake

As long as the addon has been made correctly and you have followed the steps above, the addon should be loaded next time Garry's Mod starts. To check without actually starting a game, click 'Extensions' on the main menu and then click 'Addons'. The name of the addon should be somewhere.

Earlier versions of Gmod (Like Gmod 9) work slightly differently, but theres plenty of forums/sites out there to help if you google it.