Shabad Guru is a foundational Sikh Dharma practice. Reciting Shabads in the original Gurmukhi types codes into the brain that produce a profound impact on consciousness, cutting through the negativity that lurks in the subconscious. 

Shabads are most effective when sung or recited in the original Gurmukhi, as meditations in their own right. Shabads can be  practiced for 11, 26, 54 or 108 repetitions. Many Sikhs use a mala to keep track of their recitations.

At the end of the last repetition, repeat the last two lines twice. It’s great to pick a Shabad and practice it daily for 40 or 90 or 120 or 1000 or more days. You can recite a Shabad just about anywhere. Always be conscious treat this practice respectfully. It is important to cover your head when reciting a Shabad. Reciting Shabads in the original Gurmukhi makes such a great impact on consciousness that the head needs be covered, preferably with white cotton, to provide insulation. 

Although chanting Shabads is a Sikh practice, you do not need to be a Sikh to practice Shabad Guru. 

~~Resource: the book Sikh Spiritual Practice: The Sound Way to God (2010) by Siri Kirpal Kaur Khalsa.

Note: simply listening to the Shabad Guru by playing Gurbani Kirtan on YouTube or other sources can be uplifting, in addition to or instead of a formal recitation practice, and may be a good way for beginners to get started.