The whole concept on meditation on this day is that it shall help one to cleanse the negative energy that surrounds them. Slowly allowing them to expand in the universal light of pure consciousness and connect to the energy that is itself expanding for connection with you.

Practitioners shall find few experiences that may be mystical, spiritual or religious in nature but the whole essence is the inner cleansing that happens.
The whole purpose of cleansing and channeling is to remove blockages and allow the energy to flow smoothly within the body without creating any harm to the practitioner.

Privacy as an individual is not for it is working on your energy body, re-energizing them so that it fulfills the required need of them. No personal information or scanning of the sub-conscious mind is done for the purpose and activity to balance the energy and not about probing into personal details.
No it is not a religious ritual for it is connected with Energy, Matter and Conscious. Non-religious chant is provided allowing one to connect to that one that which does not confirm to any deity or form. Shivaratri in reality is a existence of no time no space and no conscious.

It is really wrong to call Shiva as a deity for it is means that which is not, that which never was and that which never confirmed acknowledgement. For me it is a time for becoming a medium to the Divine Energy in the manner I learned to go to the core of existence into the vast nothingness. The core that I gain access is not more a sparkle that I live in forever, for I was born from there and in that existence I live like the sparkle.
Yes it can be done from home. The details of the meditation are provided through whatsapp group.