Formal:
* Gusto kita. (Most direct and neutral)
* Nagugustuhan kita. (More polite and a bit softer)
* May gusto ako sa iyo. (Literally "I have a liking for you")
Informal:
* Gusto kita, eh. (Adding "eh" makes it more casual)
* Type kita. (Slang for "I like you," literally "I type you")
* Crush kita. (Means "I have a crush on you")
Romantic:
* Mahal kita. (This means "I love you" but can also be used as a very strong expression of "I like you".)
* Ikaw ang gusto ko. (This emphasizes that you like the person specifically.)
Remember: The best way to say it depends on your relationship with the person and the situation. If you're unsure, it's always better to err on the side of formality.