Tools

ROSS (Credit goes to the author, search eAthena to find the thread)1

Sprites for palette editing

Palette packs are optional. This is the palette pack for RMS, found in eAthena forums2

Step 1: Download and extract ROSS and note the file paths to the sprite you will use. If you want to be lazy just make a copy of the file and drop it in the ROSS folder. Same for any palettes you want to edit.

Step 2: Open the RagnarokOnlineSpriteStudio.exe program. It's the one with the lunatic icon.

Step 3: Click the "Sprite" menu on the tool bar and select open. Navigate to your sprite.

Step 4: Double click the palette box you wish to edit and you will bring up the classic paint color selector. If you plan on doing multiple palettes with the same color set in one sitting, I suggest setting the colors for custom colors. Be warned though, they will revert back once you close the ROSS tool.

Step 5: Once you finish editing your palettes you need to save it. I suggest looking at the Reference Sheet I made for naming. Click Palette, then save, then navigate to the directory and enter the name. It will automatically be named a .pal

Step 6: To open a palette, click Palette, then open, then navigate to the palette you want to open, then click open or double click.