To be a true kriya yogi you don’t necessarily need to read Autobiography of a Yogi by Paramhansa Yogananda or any other book as such. You need to practice gently seven kriya steps. According to Shiva Samhita reading useless books on yoga is the first hindrance of Kriya Yoga. The second hindrance of course will be looking for a Guru or Kriya teacher. All Kriya teachers are not good. Of course there are exceptions. You can judge that yourself on time, as you progress. There are plenty of books in the market, but spending too much time on books are not at all fruitful. Most of them will confuse you.
The best is, practice the steps slowly at a comfortable pace at your own.
Our body (Microcosm) is said to be a small sample of the universe (macrocosm). The whole body of a big tree is hidden in a tiny seed. In a small sperm lies the cast of the entire human body.
There are seven lighted jewels in our body.There are Seven steps in Kriya Yoga.
Step #1 : Know your Seven Energy Bodies
Step #2: Know Seven Bija Kriya Mantras for seven energy vortex
Step #3: Know Seven Astral Planes of existence
Step #4: Know Seven master Postures of Yoga
Step #5: Know Seven Yoga Foods to activate centers
Step #6: Know Seven Breathe and Mind fluctuation energy
Step #7: Know Seven Spiritual Grace centres in brain
Out which the sixth steps which is known as Kriya Pranayama is most vital is explained here.