I'm a Pakistani working here in Macao SAR, China. How can I apply for a tourist visa to Hong Kong and what do I need to do? I just want only to visit and look around.
How can I get a visa to Hong Kong in one day?
You can apply to the Office of the Commissioner of the Ministry of Foreign Affairs of the People's Republic of China in Macao Special Administrative Region (the de facto PRC Embassy). Details are here. Address is:
Address: No. 992 Av. Dr. Rodrigo Rodrigues, Macao
It's also possible to apply directly to HK immigration by post, but the process appears to be much more lengthy.
Probably a travel agency would also be able to sort this for you, for an additional fee, of course.
I suspect you can't get it in one day. It is obvious, from your question, that you've never done this before. So you're not prepared. You probably won't have all the documentation requires, and if you show up at the visa office, you're going to waste time.
Then, your country may or may not be on the list of countries eligible for express visas. If not… you're out of luck.
The only way to get a visa quickly and effortlessly is to go through a travel agency. While they won't have much experience with HK visas (it's quite rare for Macao residents to need one), they'll have plenty of experience with the visa office, and know what to do.