From the home screen, tap the Menu key.
Tap System settings.
Tap Data usage.
To change the displayed usage cycle, tap the Data usage cycle drop down.
Note: The usage displayed on the data usage settings screen is measured by the phone and may differ from data usage shown by the carrier. This feature should be used as a guide to track usage, but is not guaranteed to prevent additional charges.
Tap the desired cycle to view.
To change the cycle reset date, tap Change cycle.
Scroll to the preffered cycle reset date and tap Set.
The cycle reset date is now changed.
To set a data limit, tap to check Set mobile data limit.
Read the Limiting data usage prompt and tap OK.
Tap and drag the horizontal limit and warning sliding bars from the right side handle to set each to the preferred level.
Note: To view data usage for a specific time period during the current cycle, tap and drag the vertical bars from the bottom handle to set the preferred date range.
To limit the data usage of individual applications, scroll to and tap the desired application.
Scroll to and tap to check Restrict background data.
Note: If Restrict background data is not available, this item cannot be restricted.
Read the warning prompt and tap OK.
Tap the Back key.
The data usage settings are now adjusted.