Usually I would use two ways: 1 «ты — счастливчик» or «ты — счастливица», if I am speaking to a woman. 2 «Тебе повезло» Munko’s variation of «ты — везучий» is used often as well, I heard it many times. Which one to use is really a matter of personal preference.

thank you for your answer ^____^

There are several ways to translate this: "ты везунчик", "ты везучий", "ты удачливый" and probably even more. Usually, I would go for "ты везучий".