The trick is to run to the central of the bridge in the Undead Burg which are guarded by the red drake and quickly turn around and back down to the stairs to safety. The drake will burn the 5 hollow soldier in the bridge gaining 555 souls. And then jump back to the bonfire, rest, and repeat.
Well that doesn't mean much if you are greedy, but you can finish this trick in about 30 second normally and the most important it's very safe. The only way to get you die while doing this trick is by dallying in the central of bridge and let the drake burn you. You don't have to fight anything, that's why this is one of the most safest trick for beginner. All you need to do is climb, run, and jump.
To access this trick you must already defeated this boss
Since the drake is the one who does the killing for us, the only recommendation and tips are
1. wear light armor
2. avoid using heavy weapon or bow, crossbow and their friend (to avoid being killed in case you miss hitting the attack button where the drake is)
3. Stay safe
Well may be you want to watch the video explaining the same thing as I did
