First make sure you get a memory card for your device. One of the most important accessories you can buy is a memory card and doesnt cost much nowadays.
It gives you room to store all those ringtones, videos and MP3s that would otherwise eat up your device memory.
The overall and most obvious way to free up memory is to delete the applications on your device that you do not use. To do this, from your BlackBerry home
screen press the Menu key, then go to Options > Advanced Options > Applications Free Up Memory!

Select the unused app and press the......

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