Secondly make sure you have installed Self compile
Locate csgo/addons/sourcemod/scripting/ and you will see a file named spcomp.exe. To compile a plugin simply drag and drop the .sp file of the plugin onto the compiler. If the compile was a success you should now have the myplugin.smx file.
Now simply move the .smx (not .sp) file from csgo/addons/sourcemod/scripting/ to the csgo/addons/sourcemod/plugins/ folder.
Note: If you are configuring your server via FTP you will not be able to drag and drop the file. You will need to copy you server contents to your local machine to do this.
Secondly make sure you have installed Self compile
Depending on your Linux version you need to install the libc6 and libstdc++6 32bit libraries before you start to compile. Example for Ubuntu: apt-get install libc6:i386 lib32stdc++6
Then use: ./compile.sh myplugin.sp. If the compile was a success you should now have myplugin.smx located in a new folder called compile.
Now simply move the .smx (not .sp) file from csgo/addons/sourcemod/scripting/compiled/ to the csgo/addons/sourcemod/plugins/ folder.