Let me tell you about my first visit and see how much I can help you!
Take your things with you when you go. There is no need to bring a lot of things. Buy some fruits appropriately. Just bring a little boxed tonic empty-handed. After all, people take care of you, not your things. Children depend on their age. Buy toys for the older ones, clothes for the younger ones, and discuss with your girlfriend.
What you should pay attention to is to smile, always keep it, it's sweet to see people, and ask your girlfriend if you don't know what to shout. Pay attention to your address when you speak, and use appropriate words and actions. When you meet for the first time, talk as little as possible and learn to listen. Look you in the eye and try to help. Don't be nervous, it will make people think that you are too affected.
Stay at night and listen to instructions. Never sleep separately, and never sleep together separately.
Behave yourself!
Wish you success!