How to add simulator iPhone XS in Xcode 9.2 also iPhone XS max

I need to build my app on an XS device. I am using Xcode 9.2.

How can I add the XS modal in my Xcode externally?

In my simulator I have up to iPhone X.

My machine Version:

OS X version: 10.12.6 (16G29)
Xcode version: 9.2

Simple solution:

1. Open Xcode.
2. Select the "Window" menu.
3. Select "Devices and Simulators".
4. Select Simulators tab.
5. Click on the "+" icon at the left bottom.
6. Choose the desired device & preferred iOS.
7. Click "Create".
8. Enjoy :).