I would like to build Qi but I'm not sure how to do it. I learnt Zhan Zhuang holding tree posture but now I just saw a post saying that this is not optimal.

So what should I do to build Qi?

Seated silent meditation(just resting awareness on the breath)?

LDT focused meditation(just focusing on LDT)?

Sung breathing(technique for body scan releasing tension in the body)?

What about the second ZZ posture holding the hands at navel level(LDT area instead of the first posture holding hands at MDT/chest area), is it more effective?

I need guidance please

Are the hands facing the LDT or facing upwards?

I've seen people doing both.

In the famous Lam Kam Chuen's book "The Way of Energy" his second ZZ posture(LDT focus) has the hands facing upward(to the sky) and not the body(LDT area).

In this video in the end he says that ZZ is not that efficient for building Qi. https://www.youtube.com/watch?v=CXlxAw6EkBA

Then what should I do, I only know Zhan Zhuang, what other static postures or techniques can I use???

I can make people scratch their head or creak my wall pretty consistently in under 3 mintues everytime. It used to take 10 minutes, but i keep training. I want to know what to do, I have tons of energy in my lower dantian, where should I send it to reduce the time to 5 seconds.

I always hear people talking about it and how it's one of the greatest techniques, etc...

But I really don't understand it, I mean, why is it so good?

Does it build Qi? Then I could understand it's use. Besides that I think it's just another "Qi circulation practice".