攝大毘盧遮那成佛神變加持經入蓮華胎藏海會悲生曼荼攞廣大念誦儀軌供養方便會 3.16

3.16

The mantra practitioner should first establish
the circular altar within their own body:
from their feet up to the navel
forms the great vajra wheel.
From there up to the heart,
one should contemplate the water wheel;
above the water wheel is the fire wheel,
and above the fire wheel is the wind wheel.
Next, one should be mindful of Dharaṇīṃdhara
and depict the various forms,
extensively as in the 'Chapter on the World'.
The practitioner of mantra
then gathers and draws the lines all around.