Create partition your Android’s SD card for increasing internal memory.

One of the main benefits with having root access on an Android device with a limited amount of internal storage such as the HTC Desire, is support for A2SD+. Of course, with root access, you also gain full control over your phone, can install a bunch of great apps only available to root users, and you’ll have the option to flash superb custom ROMs (with A2SD+ built in).
A2SD+ is an extension of Froyo’s native support for installing apps on the SD card, but it virtually installs every app to the external storage. You can more or less expand your internal storage with the size of the partition you create on your memory card — because you need to partition your SD card to use A2SD+. The easiest way to do this is with the free app ROM Manger: just make a backup of your SD card, launch the app, select the Partition SD Card option, restore all your files from the backup and that’s it.
But the largest partition ROM Manager allows you to create is unfortunately 512MB. If you’re a big fan of apps, and enjoy trying out massive ROMs from time to time that require a large EXT2/3/4 partition on your SD card, 512MB isn’t big enough. That’s when GParted comes in handy, but it’s not that user-friendly - hopefully this tutorial will help. Please note that you likely need to perform a hard-reset after partitioning your SD card with this method.
So what exactly is a partition, some might wonder? It’s a part of a hard disk, or a SD card in this case, that’s separated from the other parts. Think of partitioning as dividing your SD card into two sections that have different purposes. Don’t let the length of this tutorial scare you; the process is easy and pretty quick if you follow the instructions.

How to partition your Android’s SD card with GParted

Before we begin, make a full backup of your SD card by copying its contents to your computer, because partitioning your SD card will erase everything that’s on it. If you’re familiar with ClockworkMod Recovery or similar, you may want to make a NANDroid backup as well. You likely need to perform a hardreset once you have partitioned your memory card, and then the backup will come in handy.
1) Since GParted is designed for Linux, you need to create a bootable USB flash drive with GParted on it if you’re using Windows. This is done with a free desktop app called UNetbootin, and it’s very easy to use. It doesn’t require an installation: just launch the .exe-file and you’re ready to rock. You could create a live CD instead, but when using a USB flash drive you can simply erase the GParted files from it when you’re done.

2) Download the GParted stable release ISO .
3) Launch Unetbootin, and ignore the Distribution option at the top. Select ISO from the Diskimage drop-down menu, and click on the button with the three dots (“…”) to the right, and locate the GParted ISO you downloaded earlier.
4) Make sure your USB flash drive is selected at the bottom of the window, and press OK.
5) When UNetbootin has finished preparing the files, reboot your PC or laptop (x86) with the USB flash drive inserted. Depending on your system’s BIOS, you may need to hold down a key in order to access the boot menu. On my PC, it was F8. It could also be F2, F10 or a similar key. In the boot menu, select your USB memory stick from the list of available drives. It may be listed as a hard disk, instead of a removable disk. If you’re unable to bring up the boot menu by pressing a key, enter your BIOS (usually by hitting Del), and change the boot order.
6) Select GParted Live (Default Settings) and hit the Enter key.

7) Select Don’t touch keymap and hit Enter.

8) Select your preferred language by entering a number from the list, and confirm your choice by hitting Enter.

9) Next, you’re asked about the mode. Select (0) Continue to start X to use GParted automatically and the environment will launch.

10) Connect your Android device to your computer with an USB cable, and mount your SD card as a disk drive (usually done from the notification bar).
11) In order for GParted to discover your SD card, close the program by clicking on the X in the upper-right corner of the window, and then start it again, or select Refresh Devices from the GParted menu. This is what the GParted window looks like:

12) In the upper-right corner of the window, select your SD card from the list of available drives. Make sure you’ve selected the correct disk, by checking that the listed size matches the size of your memory card.
13) If there already are partitions available, they will be listed in the main window. Right-click on each partition and select the Delete option. You may have to choose to unmount them first, but that wasn’t the case for me.
14) Right under GParted’s toolbar, there should now be a long gray bar that says “Unallocated x.xx GiB“. Right-click on it and then click New.
15) From the resulting window, enter these details:
Free space preceding: 1 (that should be the lowest possible number)
Create as: Primary
New size: don’t alter this value
File system: FAT32
Free space following: this is the size of the partition you want to create. For 1024MB, enter 1024.
Click Add to create the partition.
16) The partition you just created, “New Partition #1”, should now be listed in the main window. Right below the new partition, it should say “Unallocated x.xx GiB”. Right click on this item, and select the New option again. From the resulting window, enter these details:
Free space preceding: 0
Create as: Primary
New size: don’t alter this value
File system: select either ext2/3/4 , depending on the type of partition you want to create. You can read more about the various partition types at Wikipedia. Since ROM Manager creates EXT3 partitions, I selected the ext3 option.
Free space following: 0
Click Add to create the new partition.
17) From the Edit menu, click Apply All Operations to apply the changes you’ve made.
18) GParted will likely refresh the list of drives at this point, but just close it down.
19) From the notification bar on your phone, unmount your SD card and quickly turn off your device. I recommend that you turn it off before Android realizes the entire SD card has been erased, or the system might say your SD card has been damaged.
20) If you already had a EXT2/3/4 partition on your SD card, and you were using a custom ROM that took advantage of that partition, I definitely recommend that you perform a hardreset right away. Otherwise your SD card may be corrupted. The first time I used GParted, I didn’t perform a hardreset, and I waited a bit until I turned off my phone after the process, and I got a “SD card blank or has unsupported file system” message. I also had a hard time formatting my memory card again the regular way.
Hence, a hardreset is preferable: when you start your device, press and hold the Volume down hardware button and the Power button at the same time. Use the volume keys to highlight the Recovery option from the screen that appears, and then press the Power button to select it. I have ClockworkMod Recovery installed, and used its excellent hardreset option to restore the firmware to its original state. If you created a NANDroid backup earlier, restore it, and also restore the files on your SD card from the backup on your computer.
Good luck, and if you have any questions, just leave a comment and I’ll be glad to assist.