Guangzhou airport has direct shuttle bus to Panyu, if you must have to go Shenzhen Airport, that should be a bit complicated. You find find the long-distance shuttle bus from Shenzhen airpoer to Dongguan (South Bus Station). There are bus to Panyu's Shiqiao Bus Station. It takes one hour from Shenzhen Airport to Dongguan Terminal (Dongguan South Bus Station) and then nearly 2 hours from Dongguan to Panyu.The cost is about 35 45.