Plan to visit Shanghai for 3 nights/4 days in August 2016. I think I need VISA. When to apply by?

Hi Barbara, as you said you'll spend 3 nights and 4 days in Shanghai, I think there is possibility that you do not need the transit permit. In Shanghai, the 72-hour period under the free transit rule counts from 00:00 of the day following your arrival, so you actually can stay longer than 72 hours.

In case that you do need to apply for an entry permit in advance, you can download the application form on the webpage of any embassy on this website. The link is given at the top position of the page.