LG D838 User Manual page 26

Getting to know your phone
To format the memory card:
Your memory card may already be formatted. If it isn't, you must format it before you
can use it.
NOTE: All files on your memory card are deleted when it is formatted.
1
Touch to open the application list.
2
Scroll and touch
3 Touch Unmount SD card.
4 Touch Erase SD card > Erase SD card > Erase everything.
5 If you have set a pattern lock, input the pattern lock then select Erase everything.
NOTE: If there is content on your memory card, the folder structure may be
different after formatting, as all the files will have been deleted.
26
Settings > General tab > Storage.