How to get the metro from Baiyun Airport to Lido Hotel? What line must to take and stop?

Take subway line 3 at the airport, get off at Yantang Station. Then transfer to line 6 to Beijing Road Station, Exit B. The whole way takes around 50 mins. It costs CNY 8 per person. After arriving, walk north around 330 yards (300 meters) to find the hotel.

Thanks Glace..
how about the ticket price for the kids 4year?

Well, child fee depends on height instead of age. It is regulated that a child shorter than 3.9 feet (1.2 meters) can ride free, but he/ she must be accompanied by an adult. If taller, your kid should pay the full price as adults.