This is one of the topics you may be questioned on if you going to take 70-689 exam. Basically, apart from just installing device driver from some media or pulling it from Windows update you may also preload drivers for your devices in advance. There are 3 ways of doing this:
Add/remove drivers to an offline image by using DISM. When using this approach you adding drivers into offline image prior to booting OS. Drivers either reflected (i.e. copied into image according to the information in .ini file) or staged (i.e. added to driver store) into image. Boot-critical drivers are reflected, all others staged. Command to add driver looks as follows:
Dism /Image:C:testoffline /Add-Driver /Driver:C:driversmydriver.inf
Important switches to be aware of are /recurse (to add all drivers from the folder) and /forceunsigned (to add unsigned driver). Please refer to the Add and Remove Drivers to an Offline Windows Image article on TechNet for details.
Add drivers during an automated deployment by using Windows Setup and an answer file. Here you should use Windows System Image Manager (Windows SIM) to create an answer file that contains the paths to the device drivers that you intend to install. There you are adding the Microsoft-Windows-PnpCustomizationsNonWinPE component to your answer file in the offlineServicing configuration pass. Then in Microsoft-Windows-PnpCustomizationsNonWinPE node in the answer file you right-click DevicePaths, and then select Insert New PathAndCredentials to add new PathAndCredentials list item.
Once you created your answer file you need to apply it to your image with DISM (first mount image, then apply):
DISM /Mount-Image /ImageFile:C:testimagesinstall.wim /Index:1 /MountDir:C:testoffline\n\nDISM /Image:C:testoffline /Apply-Unattend:C:testanswerfilesmyunattend.xml
Add drivers after deployment on a running operating system by using PnPUtil or an answer file. So in order to add device drivers into running OS you may employ 2 methods:
\nUse PnPUtil to add or remove PnP drivers. See Use PnPUtil at a command line to install a Plug and Play device for details. You can use this procedure to install the device driver for a device that is plugged in, but for which no device driver is installed.\n
Use an answer file to automate the installation of PnP drivers when the computer is booted in audit mode. See Add a Driver Online in Audit Mode for details. You can use an answer file to automate the installation of device drivers when the computer is booted in audit mode. The auditSystem configuration pass processes unattended Setup settings while Windows is running in system context, before a user logs on to the computer in audit mode.