Natural
The Natural or Neglect method is simply not brushing the hair. There are variations to this method in which seperating of the hair to keep large matted areas from forming.
Twist and Rip
Twist and Rip, or TNR is a method used to start the dreading process. The hair is separated into sections, twisted and pulled apart continuously.
Backcombing
Backcombing is the process in which the hair is sectioned and a fine metal comb is used to brush the hair towards the scalp.
Braids
With the Braid method, hair is braided and left alone.
Crochet
When done correctly, crochet can make dreadlocks look mature and maintained. Usually after another starter method, like TNR or Backcoming, a crochet hook is used to pull in stray hair. This method is somewhat addictive and can cause excessive damage leading to dread breakage.
Interlocking
Interlocking, or Root Flipping consists of the ends of the dreads being pulled through the center of the dread towards the scalp in a zig zag motion. This method causes weak spots and can lead to breakage and/or dread loss.
Twists
More common with African American hair, this process involves twisting the hair into sections. Over-twisting can cause dread loss.
If you want amazing dreads like Bob Marley, go natural.
Hear it from the man himself (after the ~10 seconds of dialog from a french reporter):
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