Go into BattleScribe, and click either "Save as HTML" or "Save Roster":
Then put the HTML/ROS/ROSZ file here and wait for a little bit (a few seconds, tops, unless you're a dick and tried a 12,000 point Apoc list, in which case what the fuck):
You should get a prompt to download a PDF that looks something like this:
Followed by a bunch of these: