Solidification of the astral body requires the use of vital and elemental energy.
Within your astral body, you call into your body the elements through imagination and feeling. You then call into yourself more Earth element than the rest to allow yourself to sink down to the earth plane.
Finally, akashic energy is allowed within your body by absorbing it as well through imagination and tactile sensations.
This will allow people to see you physically as long as you have tuned yourself to the earth enough.
With more bodily control, it would be possible to cause things to happen or being able to take another shape since you’re pure energy.
Manipulation of light itself allows you to change to whatever form and color. Sound could be heard as well depending on how solid of a form you are.
The creation of everything is through sound and light.