This is a regular verb. It follows the conjugation pattern of the verb hablar.
Present:
Me baño por la mañana.
I shower in the morning.
Preterite:
Ayer nos bañamos en el mar.
Yesterday we swam in the sea.
Negative Imperative:
No se bañen aquí; la corriente es fuerte.
Don't swim here; the current is strong.