This Saturday February 18th sunset to Sunday Sunrise is the Vedic Holy celebration of Maha Shivaratri. Whereby yogis and seekers worship the great Lord Shiva. Take note of this night, and if you practice any meditation or yoga, wake up early, or stay up late to offer your practice on this auspicious night.
If you do not know any mantra you can search for a Shiva mantra on this YOUTUBE channel:
Here is a short video speaking off Maha Shivaratri