Instructions
Download the SourceMod installation package, which can be found in Resources. Make sure to download the correct package for the operating system that your server is running. "Team Fortress 2" servers can either run on the Windows or on the Linux operating systems.
Right-click on the file you just download and select "Extract here." Then select the files with your mouse, right-click and select "Copy."
Connect to your remote server by using your remote desktop connection or a File Transfer Protocol (FTP) client. Then navigate to the folder that contains the files of the Source Dedicated Server (SRCDS) application that helps run your "Team Fortress 2" server. Typically, you can find the SRCDS files in the following directory: C:\srcds
Navigate to the following folder inside your SRCDS folder: orangebox\tf\addons. Then right-click anywhere in the folder and select "Paste." Windows will now paste the files you previously extracted and copied.
Close your remote server connection and launch "Team Fortress 2." Connect to your server and press the "~" key on your keyboard to open the developer console. Type "meta list" in the console and press the ENTER key. If the console displays a new "SourceMod" line, you have successfully installed SourceMod on your server.