Today a XDA Developer has released the Rooting Tool which will help you in rooting your device in an very easy way..!!
That's Pretty Fabulous, you can read many guides online regarding the rooting process and download.. some of them are:
Root, SafeStrap Recovery, etc. With Motorola Droid 4 Utility Tool
Droid 4 Utility For Windows: Root/Unroot Motorola DROID 4 On Android 2.3.6/4.0.3, Boot Into Recovery/Fastboot, Install Safestrap & More! | Redmond Pie