您需要使用 Xcode 8 Beta 中的 DeveloperDiskImage.对于此提取 Xcode 8 Beta 应用程序，并将适用于 iOS 10 的 DeveloperDiskImage 复制到您的 Xcode 文件夹.

You need use DeveloperDiskImage from Xcode 8 Beta. For this extract Xcode 8 Beta app and copy DeveloperDiskImage for iOS 10 to your Xcode folder.

假设你将 Xcode 解压到 Downloads/Xcode-beta.app

Suppose you extract Xcode to Downloads/Xcode-beta.app

cp -r /Users/fanruten/Downloads/Xcode-beta.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport/10.0 (14A345) /Applications/Xcode_7.2.1.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport

复制 DeveloperDiskImage 后，您应该启动 Xcode 并将 iOS 设备连接到您的 Mac.

After copy DeveloperDiskImage you should start Xcode and connect iOS device to your mac.

使用标准的 Xcode 安装可以创建一个软链接:

With a standard Xcode install one can create a soft link:

sudo ln -s 
/Applications/Xcode-beta.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport/10.0 (14A5309d) 
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport/10.0