Fixing portrait colors

[J4CKS85]

I am sorry to anonying you guys but I want to understand how a portrait is fixed

I downloaded the Vincent Valentine spr file (but it could be any other portrait)
I opened it with FFTSprite-1.0.0.3 and i export the picture

I followed the tutorial below :
http://ffhacktics.com/tutorials.php?id=10


I am blocked at the end of the step 5.
It is written : "Now it's time to fix the portrait. Hopefully you already have the portrait cropped out as a separate BMP with the correct palette. If not, proceed to do so".
Q1 : But i don't understand. How can i replaced the wrong portrait color if i don't have the good color ?
Q2 : Do I need to create a portrait with the good color before ?

Thx in advance for your answers

[Umbral]

http://ffhacktics.com/smf/index.php?topic=5991.0

has the portrait you need, ready for use.

[J4CKS85]

Thank you