Be more like a Anit-hero or self indulgent. To be a good villain you don't think "I will do evil!" you have to have reasons an motivation for doing the action you will take. One good way is to take a regular hero like losing a village or a loved one to some bad dudes and then instead of making them do good you make them out right kill people.
One way is to have him round up some bandits and pretty much slaughter them in RP it is a little harder because we can't round up NPC's but you can have a story of it or have your character be stealing money or strong arming people for information.
One way is to have him round up some bandits and pretty much slaughter them in RP it is a little harder because we can't round up NPC's but you can have a story of it or have your character be stealing money or strong arming people for information.