If you're a foreigner and want to setup a business in Hong Kong the best way to do so would be to visit Hong Kong and find a location where you wan to establish the business.
Then either rent or buy a property or building that will house your business, then you'll need to register the business in Hong Kong, setup a Hong Kong bank account and get the necessary permits.
It can be hard to establish the business in Hong Kong without you actually being there but you may be able to hire someone else to help you establish the business in Hong Kong.
But it's recommended to visit Hong Kong and then setup the business there yourself.