Meeting Andrew from the USA

Hi! I’m Anastasia from Ukraine. I’ve been a part of AFA for 2 years already. Now, I’m meeting a man named Andrew next week.
And I have a little time to prepare for it. I want him to cherish his stay here in my country!

Andrew and I have been talking over the phone for 9 months already. The phone translator of AFA has been a great help for us.
No communication barrier has been observed and the good thing is he even taught me how to speak English! Isn’t that awesome?
He is the reason why I learned to speak and write in English.

Now, back to my concern. I’ll be meeting him for the FIRST TIME! I’m a bit nervous. What should be my first word to him? Should I say “Hi”? “Hello”? Or “How are you”.
I’m asking this because I’m not that well aware of the American culture. What should I wear?
What should I do to let him feel he’s very welcome here in Ukraine?