More than one way to go about this, but the essentials are:
A PXE boot server that your DHCP server can point to
The bootable environment on the PXE server
The image file that you want to install (if this is Windows then you MUST run sysprep on the machine you take the image from)
Any post-image scripts to customise individual machines or to complete the Windows Out Of Box Experience.
If you have Windows Server then MS provides the whole thing in Windows Deployment Services (WDS)
And whatever you use to deploy a Windows image, that image will need appropriate licences and istallation media for reimaging (OEM licences and media don't work properly, you need a volume licence key)