Note: You should open Hitman with Peacock before following the steps in this tutorial. In addition, Peacock has received a new update, so now just go to localhost or 127.0.0.1 in your browser instead of localhost/loadouts. When you are on the localhost page, click on Loadout Profiles in the upper left navbar. Then proceed with the rest of the video tutorial.
To pick specific escalation levels, run Start Server.cmd from your Peacock Install folder, then open up a web browser and go to localhost or 127.0.0.1. Go to Escalation Level Picker and proceed from there following instructions on screen.