A womans hair is her natural covering...no need for covering.
Not while praying according to scripture.
1 Corinthians 11 details it.
It is written
1 Cor 11:5-6 every woman that prayeth or prophesieth with her head uncovered dishonoureth her head: for that is even all one as if she were shaven.
6 For if the woman be not covered, let her also be shorn: but if it be a shame for a woman to be shorn or shaven, let her be covered.