The time of entry on the day of arrival does not count. That means if you enter on the 1st, the 2nd is when the first day is counted. As long as you exit before 23:59 on the 8th, it's fine.
 
　　       Traveling from Hong Kong to Macau and then returning to Hong Kong (the reverse—traveling from Macau to Hong Kong and then back to Macau—is not allowed this way; you would need two separate Macau endorsements. However, currently in China you can only apply for one Macau endorsement at a time.) You do not need to use the Hong Kong and Macau travel permit again within seven days. (For example, arriving in Hong Kong on the 1st, traveling to Macau in between, and returning to Hong Kong by the 8th is okay. But you must leave Hong Kong by the 8th.)
 
　　       Apply for the Hong Kong and Macau Travel Permit without leaving home – With an increasing number of people applying for entry-exit services, some citizens have complained about long queues and waiting times. Police have stated that in fact, there are five other ways to apply for a second endorsement for individual travel to Hong Kong and Macau: online application (http://www.gdcrj.com), telephone application (call 11185 from a landline), SMS application, application at postal service outlets, and self-service machine application.
 
　　       The introduction of the above policies has greatly promoted the development of independent travel to Hong Kong, travel to both Hong Kong and Macau, and group tours. Xie Bo, head of HowToTrip (www.uuyoyo.com), the largest online travel booking website for Hong Kong and Macau in South China, said: With the May Day holiday approaching and the peak season for travel to Hong Kong and Macau in full swing, HowToTrip is fully prepared to provide travelers with even higher-quality travel services to Hong Kong and Macau.