Step 1: Download and install Motorola Drivers for your Windows PC (this doesn’t work on other operating systems): 32-bit or 64-bit.
Step 2: Download DooMLoRD_v2_ROOT-zergRush-busybox-su.zip and extract contents to your PC (desktop would be a good place).
Step 3: From your Droid RAZR’s homescreen, tap Menu button and enable USB Debugging from Settings > Applications > Development.
Step 4: Connect your Droid RAZR with your PC and select Charge Only option from notifications drawer.
Step 5: Navigate to where the folder you unzipped in Step 2 to and open the folder and click on the runme.bat file and let it do its thing.
If you are unfamiliar, the new 7.3mm wide Motorola Droid RAZR features a 1.2GHz dual-core CPU, a 4.3-inch qHD Super AMOLED display with qHD resolution, 1GB RAM, Android 2.3.5 (Gingerbread) and an 8-megapixel camera with dual-LED flash.