Prostration (Tib. ཕྱག་འཚལ་, chaktsal, Wyl. phyag 'tshal) is the first of the seven branches, and is described as the antidote to pride.
Prostration (or homage) in Tibetan is chak tsal (Wyl. phyag 'tshal). According to the oral lineage, the first part, chak (Wyl. phyag), means something like ‘sweeping away’ any harmful actions and obscurations, just as we sweep away dirt and dust using a broom. Then, tsal ('tshal), means that we receive the blessings of enlightened body, speech and mind, and gain all the siddhis.
So what do we sweep away and receive?
In most ngöndro practices, prostrations are combined with the practice of taking refuge, but in the Longchen Nyingtik Ngöndro they are combined with the Guru Yoga.