Kodo Sawaki was known for his rigorous emphasis on zazen, in particular the practice of shikantaza, ie just sitting. He called Zen "wonderfully useless", discouraging any idea of gaining or seeking after special experiences or states of consciousness.
This poster describes one way of proper zazen (meditation) posture. Many beginners start with one session per day for 20 minutes. Gradually, a second 20 minute session is added. Many long term practitioners work up to one session 1 hour per day.