Your “two cents” is far more valuable since it is truth - very well explained for beginners.
Hindu Gods use yantras which are quite complex to sigils in my opinion.
The one yantra I meditated on, unconsciously opened a portal located on my spine.
It was not a pleasant experience.
But evocation is a bit tricky as it is said the God chooses you which then allows you to open up in either trance ( especially during prayers like kavady or Kali midnight prayers) or they visit you when you dreaming.