China has has spread contagion to Europe and the United States.
What To Do Now?
Consider not selling existing good positions into this panic sell off.
Consider NOT buying aggressively.
Consider continuing to hold large amounts of cash.
Consider not acting out of emotion.
Understand that 2013, 2014 and the first half of 2015 have been unusual in terms of low volatility.
No one, including you, knows with certainty what will happen next.
Stock market indicator is very negative