Basically buy grain and give it to your chosen faction's people when they ask for stuff. Handouts, like flattery, get you everywhere in life.
Ah, yes bounty hunting. Just find a system with ~5 political powers and your chosen one being easily identifiable, and the rest being different, like commies or something. Then go to the Nav Point. When you see someone who is Wanted check your left pane to see who they belong to; if it's your people, ignore them and wait for another target. BLAM! Might work - I was meaning to be doing that but I've been pretty indiscriminate and just love shooting things. Should work though.