I have a lg 4lte and I installed a sd card how do I change from internal memory to the sd card?

[AC Question]

I have tried to download a root software but it would not work on my lg 4lte cell phone.

 

[Rukbat]

External (SD card) storage is designed for storing songs, pictures, etc. You don't "switch" from using one to using the other, except in apps that allow you to change where they store their data.