For Indonesian passport holders, no visa is required if they stay in Hongkong for less than 30 days. So you can go to Hongkong firstly and apply for the visa for your helper from the HKSAR when you are in Kong kong, which will be easier.

Ms Chan, you mean a visa with 6 months validity or a duration of stay for 6 months? Actually, your Indonesian domestic helper (valid Indonesian passport holders) can visit Hong Kong without a visa for up to 30 days. Since you are a HK citizen,you can issue an invitation letter (you act as a local sponsor).Other basic documents like valid passport, HK visa application form, latest bank statements and air tickets are also required. It often takes four working day to get your visa processed.