This is a regular verb. It follows the conjugation pattern of the verb falar.
This verb is more common in European Portuguese. In Brazilian Portuguese, registrar is preferred.
Present:
A Ana regista cada gasto em um caderno.
A Ana regista cada despesa num caderno.
Ana records every expense in a notebook.
Preterite:
O Miguel registou a empresa no ano passado.
Miguel registered the company last year.
Conditional:
A Clara registaria essa ideia antes de esquecer.
A Clara registaria essa ideia antes de a esquecer.
Clara would record that idea before forgetting it.