Iphone3 Transfer To Iphone4

[avalone]

I have an iphone3 and have been given a second hand iphone4. The iphone 4 has a smaller SIM card than my iphone3. Can I transfer the information on my iphone3,such as photos,contacts and mobile number, to the iphone4?
I am with O2.

[Milvus]

Ask O2 to send you a Sim for the iPhone 4 keeping your number.
Connect your old phone to iTunes on your computer using your charging cable, Back up your data to iTunes. Connect your iPhone 4 to iTunes in the same way and click restore from backup all you data, music, photos will be reloaded to your new iPhone

[Milvus]

Sorry, that should read - All your data, music, photos will be reloaded to your new iPhone.

[stoofur]

You can if feeling brave actually cut the sim card to fit.

[avalone]

Thanks for excellent replies.Much appreciated.