I have a question regarding uniforms of Texas rangers in the army of the Trans-Mississippi,

I am aware that uniforms among the Texas cavalry were lax to say the least, many men just wearing regular civilian clothes, however, I am curious as to how denotation of rank would work in that situation? Would soldiers sew on rank Chevrons they captured from the union? Would they make their own out of spare or bought material? Or were you just expected to know the face and voice of your NCOs and COs in the heat of battle? This is all rather confusing to me.

Regards to you all,