Talk to Captain Bezique at the west exit of Gludin Village. He will give you Bezique's Letter.
Take the letter to Neti, who is in the southwest building of the north half of Gludin. She will give you Neti's Dagger and Neti's Bow. You can ONLY use these two weapons during the entire quest - so bring lots of soulshots as they are weak weapons against the undead.
Go to the Ruins of Sorrow (Grim Ruins on the map). If you walk from Gludin, it's the (only) north branch off the path before you turn east to Gludio. Hunt the Spartoi (with the dagger or bow) anywhere in this area or to the northwest of the walled ruins until you collect 10 Spartoi's Bones. You can also hunt the Skeletons but they only rarely drop the bones.
Give the bones to Neti and you will get a Horseshoe Of Light.
Give the horseshoe to Captain Bezique and he will give you a Wanted Bill.
Hunt Cat's Eye Bandits (lvl 15 passive) - with the dagger or bow - until you collect the 4 stolen items; Stolen Necklace, Stolen Tomes, Stolen Jewelry, Stolen Ring. They are along right side of the road from Gludin to Gludio, near /loc -49k, 147k and north. Bring some friends to deal with all the other Ol Mahums (up to lvl 30+), or just be very careful to find the bandits alone.
Talk to Captain Bezique. He will take all the quest related items, and give you Bezique's Recommendation which can be used to make the transition to Rogue once you are level 20.
Talk to Grandmaster Ramos in the trainer building at the north end of Gludin to become a Rogue.