Peplink 310 IPSec VPN with TMG

I have a client that has a Peplink 310 in the branch and a TMG (Microsoft) at the headquarters of his company. He wants to connect the two points through the IPSec VPN.
Do you have any step-by-step or tutorial to set up a Peplink to connect to a third-party equipment via IPSec VPN.
Can you help us?
Thanks!