What Android version are you running?
If the OS supports it, it's a matter of selecting an app (Settings > Apps > Downloaded, select app) and if the app can be moved (not all can) selecting "move to SD". Unless LG have hacked it back in it was removed early in Android 4, so if none of the apps even have a move to SD button then that's it for doing it officially. Google's idea these days is that removable cards are for media.
There are still ways if you root the phone (as was also true before Google introduced the official version in Android 2.something), but if it's not there then there's no way without rooting.