Here's a really easy video about how to back your photos on the phone itself
To restore just open the app after the reset and the photos will come back

Back Up App Data:

1. Launch “Settings”
2. Go to the “General “tab
3. Tap “Backup & reset”
4. Turn “Back up my data” ON

Back Up Contacts on the SD Card:

1. Open “Settings”
2. Access the “General” tab
3. Tap “Backup & reset” > “LG Backup”
4. Tap “Backup & restore” > “Back up data”
5. Tap “SD Card”
6. Select the contacts you want to back up
7. When prompted with “Backup completed”, tap “Done”

Back Up Contacts on an LG Account:

1. Open “Settings”
2. Access the “General” tab
3. Tap “Backup & reset” > “LG Backup”
4. Tap “Backup & restore”
5. Tap “Back up data” > “LG Cloud”
6. Sign in with your LG account
7. Enable “Personal data” and deselect the other options
8. Expand “Personal data” and make sure “Contacts” is selected
9. Tap “Start” > “Done”

Back Up Media Files on the Phone Storage:

1. Launch “Settings”
2. Access the “General” tab
3. Tap “Backup & Reset” > “LG Backup”
4. Tap “Backup & Restore”
5. Enable “Media data” and disable the other options if necessary
6. Tap “Start” > “Done”

Back Up Media Files on a Windows Computer:

1. Connect the LG device to your computer via USB
2. Enable “Media device” / “File Transfer” when prompted or from the “Notification” area
3. Launch the File Explorer on the computer
4. Locate and copy the media files on the phone
5. Transfer the files in the desired backup location on the PC
6. Once the transfer is complete, eject the phone storage via system tray and safely disconnect the phone from the USB port