Formal:
* Tenha um dia abençoado: This is the most direct translation and is appropriate for formal situations.
* Que o seu dia seja abençoado: This means "May your day be blessed" and is also formal.
Informal:
* Tenha um bom dia abençoado: This is a more informal way of saying "Have a good blessed day".
* Que Deus te abençoe hoje: This means "May God bless you today" and is a common informal greeting.
Other Options:
* Tenha um dia cheio de paz e alegrias: This means "Have a day full of peace and joy" and is a more general well-wishing.
* Que a felicidade te acompanhe hoje: This means "May happiness accompany you today" and is also a general well-wishing.
The best option for you will depend on the specific context of the situation.