Are you rooted?
What rom are you running?
You need to keep your screen brightness turned down as far as you can.
Also ... i leave 3g turned off until i need it, and sync off, i just check email once a day or there is an app that will turn sync on when you want, you can set it up how you like.
You just have to be diligent about your phone settings to save battery life.
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Failing to prepare ,is like preparing to fail.
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