In SynergyCP, locations are referred to as IP groups. Each location typically consists of 1 PXE DHCP server and 1 or more PXE file servers, though you may need multiple IP groups in the same location if you have networks with multiple carriers or similar.
Preparing the on-site Synergy server(s)
First, install the file server. Then setup the DHCP server, which can be done on the same server or on a separate one (a small VPS should be plenty, even for large numbers of servers).
wget https://install.synergycp.com/bm/pxe-dhcp-server.sh -O - | bash
Configure the network at that location such that all servers that SynergyCP is responsible for DHCP boot to the IP of the PXE DHCP server.
Testing that it worked
It can take up to a few hours for the files to sync, depending on the network throughput between the newly added server and its master file server. You can immediately add an IP Group with the name of the location, for instance: Los Angeles. Then add an IP entity and a server to the IP Group and test an OS Reload on that server. If it makes it to 40% DHCP is correctly configured. If it doesn't make it past 40%, then the file server is most likely still syncing files. You can retry the install at any time, though one OS completing does not always mean that all of the files have finished syncing. Windows ISOs typically take the longest to sync.