Before You Begin Make Sure that you have rooted your device and installed a custom recovery.
Load a Custom ROMNow that we have root access and a custom recovery image, we need to find a ROM we want to flash. Thanks to the amazing third party developers (most of which do this in their spare time), there are a bunch of ROMs to choose from. All of them have their own pros and cons and tweaks and themes, so you should try a few to decide which you’d prefer.
1. Head to any ROM Repository and find your Android device to be presented with all of the ROMs found for your device. Then follow the download links to see their features and download the .zip file for the ROM to your computer.
2. After you download the .zip to your computer, plug in your device via USB cable.
3. Copy the .zip file to the SD Card (do NOT extract it, just copy the whole zip file).
4. Unplug your device.
5. Now, open ROM Manager again.
6. Select Reboot into Recovery and wait for the device to reboot.
7. Once in recovery mode, use the volume buttons to navigate and power button to select Backup and Recovery.
8. Then select Backup and hit yes to confirm. Wait for it to finish backing up your current system (this will save you if something goes wrong).
9. Select Wipe Data / Factory Reset.
10. Select Flash zip from sdcard.
11. Select Choose zip from sdcard.
12. Find the ROM we copied to the sdcard in .zip format and select it. Then select yes to confirm. Wait for it to finish flashing.
13. Select Reboot System Now. Once it reboots (which will take a while the first time), you’ll be running the new ROM.