How to create a launcher for for JetBrains Gogland

You can try to create a desktop file similar to the rest of Jetbrains products, something like this:

[Desktop Entry]
Version=1.0
Type=Application
Name=Gogland
Icon=/opt/Gogland/bin/gogland.png
Exec="/opt/Gogland/bin/gogland.sh" %f
Comment=The Golang IDE
Categories=Development;IDE;
Terminal=false
StartupWMClass=jetbrains-gogland

Anyway, Jetbrains IDE's usually comes with a builtin option to create launcher shortcut from its startup/initial screen. I think it's the best and simpler solution.