From the Home screen, drag down the Notification panel.
Drag down the Quick settings panel.
Tap the Settings icon.
Tap Network and Internet.
Tap Mobile network.
Tap Data usage.
Tap the Settings icon.
From this screen, you can limit your data usage and set up alerts for when you're reaching your data usage limits for the current month.
Tap or slide the Set data warning switch to ON.
You can also turn off mobile data when you're in areas where you don't want to use any data.
Tap Data warning.
Tap the GB field.
Enter your preferred data usage warning.
Tap SET.
Tap or slide the Set data limit switch to ON.
Tap OK.
Tap Data limit.
Tap the GB field.
Enter your preferred data usage limit.
Tap SET.
Tap App data usage cycle.
Select a new usage cycle reset date.
Tap SET.
You've completed the steps!
