Formal:
* Magandang araw po. Ako po si Jacob. (Good day. I am Jacob.)
* Magandang hapon po. Ako po si Jacob. (Good afternoon. I am Jacob.)
* Magandang gabi po. Ako po si Jacob. (Good evening. I am Jacob.)
Informal:
* Hi, ako si Jacob. (Hi, I am Jacob.)
* Hello, Jacob ang pangalan ko. (Hello, Jacob is my name.)
More casual:
* Uy, ako si Jacob. (Hey, I'm Jacob.)
You can choose the phrase that best fits the situation and your relationship with the person you are talking to.