Say : Как дела? Or kak dela?

Как ты? Ты как ?

Как дела? Как ты? Is informal greeting. Formally we say Здравствуйте.

"How are you" is not a part of greetings exchange in Russian—at least, not between people who barely know each other. Use "Привет"/"Здравствуй(те)" and you will be OK.