Get your SMN up to 20, get Ramuh and solo Shooting Fish repeatedly (need 2hr though).
I remember only needing Ramuh, a 2hr, a Yagudo Drink and an Au Lait.
I got a few mannequin pieces out of all my runs, which sell quite well.
Pop Astral Flow
Pop a Drink
Use Judgement Bolt (or w/e it is) as soon as he gets close enough to melee.
Run down a bit
Watch your timer
If timer on JB is up, get in range, use JB, run again
If Ramuh's health gets low well before the timer is back up, make sure to run away to get enough room to resummon.
JB once more.
If the fish are still alive, just use Thunderspark and they should be dead.
Also, always a good idea to do the fight on Lightningday, just for good luck. And have as close to maxed Summoning Skill as possible.
I've soloed this one over and over. Sometimes you have bad luck, but I didn't lose often enough for me to stop doing it.
I've soloed the Wings of Fury once as a BST...wait, no...I believe I was SMN and had a BST friend with me. Much easier. Sic Carby on the big bat, let the BST fight the lil bats against each other, heal (using Carby) as needed.
FFXI: Yzerman on Bahamut server