how do you integrate a maid into the daily household life? this is my first maid, and she will always hide in her room when we gather in the living room.. end up that we need to do some chores ourselves or shout for her.. do I let her watch tv with us, sit in the living room while we play with the baby?

Set a time frame for your helper. For example, if her working hours (by this I mean when most of her usual chores are done) is till 8pm, request for her to be within the vicinity during that time frame so that you can call upon her for help if needed. She's probably shy and still trying to get a sense of your family dynamics. You can invite her to watch TV with the family or hang out with the kids while everyone is out in the living room. But if she doesn't want to, it's okay and respect her decision. She could be tired and just want some alone time to herself.