Newb Pranayama Spinal Breathing Few Questions

[LoneWonderer]

I have been reading mixed opinions online on the proper technique. Seems the core of the practice is the focus on visualization of energy from bottom of spine to crown of head. 

Others say to relax and just focus on breath coming in and out and not to visualize and that this should be enough to activate parasympathetic nervous system. Which method is correct?

Also how long are your typical sessions? I am a newb so starting with 10 min and increasing 1min per day untill I hit the 1h mark. The idea is to keep the 1h daily for 1+ years in hope of increasing baseline consciousness.

Thank you 🙏

Edited 12 hours ago by LoneWonderer