See the above picture for most of the information needed.
ANyway, at the start to get to the alley shown turn left and go backwards, and go down the little indent. When there, get as far down as possible and cast your two sprits: Energising Wind THEN Quickening Zephyr. Then, activate Serpants and activate the traps, starting with Dust and going from there. Cycle through them, ignore the zashien, and they will all come on to your traps with their pets. Usually, this will kill them, although sometimes they retreat alive and IWAY saves them. if this happens, just lay a few more traps to take them down, preferably Dust, or Spike, so you can cast a few. Its all very simple, and gets you a lot of faction and 400 or so exp! Its solo, so saves the bother of finding a team, gets you much easier faction than RA or TA, and is 100% success chance once you get experienced!
Please note you can only farm a certain amount a day like this. Its somewhere from 1k-2k, I'm sure someone in comments will put me right on this.