The Cyanogenmod 10.2 stable release came out for the Samsung Galaxy S4 Mini only a few days ago. Here's a guide from Team Android that provides step-by-step instructions on how to install the latest CM stable release onto the Samsung Galaxy S4 Mini LTE I9195. It is worth noting that users will have to first root their handsets and then install a custom recovery before actually performing this method onto their devices.
1) This tutorial is only for installing Android 4.3.1 CM 10.2 Final ROM on Samsung Galaxy S4 Mini LTE I9195. Installing it on any other variant might cause your handset to brick.
2) Users must root their handsets before attempting the installation.
3) Users must have Clockwork recovery installed earlier.
4) Users must take a back up of all their important data before attempting this installation since it will wipe out all their data.
5) Users must perform a Dalvik Cache wipe before proceeding from the recovery mode. More instructions on that in the guide.
6) Since this ROM is a custom firmware, Samsung KIES will not detect your phone.
7) Your handset should have more than 80 percent of battery life.
Step by step instructions for installation
Sep 2: By using the USB cable, connect and mount your Galaxy S4 Mini LTE USB memory on your computer.
Step 3: Users will now have to copy/paste the downloaded Android 4.3.1 ROMzip and Google Apps zip files to the SD cards. It is important that the files are stored in the SD card root and not any other folder.
Step 4: Now, turn off your phone
Step 5: Disconnect from the USB cable.
Step 6: Users must now get into recovery mode. For this, they must switch on the phone while pressing and holding 'Volume Up' + 'Home' + 'Power' buttons simultaneously.
Step 7: After having entered ClockworkMod recovery, users must perform a full data wipe. This can be done by selecting "wipe data/factory reset" as shown below. The power button must be used to make selections in the Recovery mode.
Step 8: Users must now perform a cache wipe. This can be done by selecting "wipe cache partition".
Step 9: Even though this step is optional, it is highly recommended. Users should perform a wipe of their dalvik cache. This will prevent them from experiencing boot loops and other such errors. From CWM recovery, go to 'advanced' and then select "wipe dalvik cache".
Step 10: After this, select "choose zip from sdcard". This can be done by using the power button. Once you confirm the installation on the next screen, the procedure should start.
Step 11: Now, users must install the Gapps. Repeat the above step with the Gapps file and install it on your phone.
Step 12: Once the installation is complete, select "+++++Go Back+++++". After this, reboot the phone by selecting "reboot system now" from the recovery menu.
Your handset should now have Android 4.3.1 CM10.2 Final Jelly Beancustom ROM installed
Important: Your handset might take about 5 minutes to boot during the first time, so please be patient.
[Source: Team Android]