This tutorial helps to Partition memory card of Android using ClockWorkMod. If ClockWorkMod is not present then open this link here. ClockWorkmod will be used to create two partition, one of which will be use as internal memory while the other will be used for storing your media, music, etc. Remember partitioning may not cause data loss but in any case keep backup of your data. This method uses Clockworkmod to create partitions.
If Clockworkmod is present
1. Power-off your Android Phone.
2. Restart the phone in Recovery mode. You can do this by pressing Home+Power button or Home+Power+Volume-up button (Differ in different android models).
3. Once your phone is in the Recovery menu of Clockworkmod then navigate to Advanced using volume-down key and select the option using the Home Key button.
4. Next Navigate to Partition SD Card and press Home.
5. Next you get Ext Size. This menu helps you to create a new partition. select partition of any size required by you. But the maximum partition size should be less than free memory size of your SD Card.
6. Next you are presented with a option of Swap Size. Select 0mb for this.
7. Once you select 0mb the Clockworkmod will start creating partition.
8. Once the message is displayed partition complete, reboot the phone.
Visit this link to use the second partition as internal memory. How To Increase Internal Memory Of Android Phones