First of all wrong section. Moved to "Mods < Modding Help/Resourses". Second, You need to pack your gun (for example: semi.kv6 file, semi.png file and sounds if you got any) into a zip package with
7-zip or Winrar. Then upload the package to
Mediafire or any other file sharing site. And finally put the link in the forums. Also don't forget to include pictures that you can upload on
Imgur or
Imageshack.