Note -You need to have bootloader unlocked and custom recovery like twrp installed on your device before proceeding
Unlock bootloader here
Flash the custom recovery of your choice using auto flash script included in separate attachment
1) Download and rename recovery file as recovery.img and put into the folder of auto flash script.
2) Reboot your device into bootloader mode and connect to PC using USB cable [You shold have latest motorola device manager installed and your device should indicate usb connected on bootloader screen]
3) Now open 'auto flash recovery script' folder and run auto_flash_recovery.bat file
4) Now custom recovery is installed on your device
Steps for rooting-
1. Download BETA-SuperSU-v2.62-3-20151211162651.zip and place it in root of your internal sd card (other supersu version does not work on titan running official marshmallow)
2. flash BETA-SuperSU-v2.62-3-20151211162651.zip using twrp recovery
3. wipe delvick cache and cache (optional)
4. reboot device
5. If you want to use stable super su version i.e. UPDATE-SuperSU-v2.65-20151226141550.zip or any version like any supersu beta except BETA-SuperSU-v2.62-3. download and flash it over BETA-SuperSU-v2.62 after rooting.
6. If you have previously rooted your MM running device using SuperSu-v2.52 with modified boot.img, You need to flash stock boot.img first and reboot then follow this guide (step 1-5)
#BETA-SuperSU-v2.62 will do all required modification by its own script automatically.
Note- Dnt flash any other supersu version or SuperSU-v2.65 alone on unrooted device. you will get bootloop. Do a backup of your rom before any rooting operation.
In case if u stuck on bootloop flash this update UnSu script via twrp, wipe delvick and cache and reboot. this script will remove any supersu file installed in your device thus fully unrooting ur device that will recover you from bootloop