Instructions
Create a portrait image that is 40 x 62 pixels and save it as an 8-bit BMP file if you are creating a character image. If you want an image for the character sheet, the image should be a 110 x 170 24-bit BMP. These are the only two formats eligible for use in "Baldur's Gate."
Save both files with identical names, adding an "S" for the small file and an "L" for the large one. Image names must be under 7 letters. For example, "imageS.bmp" for the small picture and "imageL.bmp" for the large one.
Open Windows Explorer and navigate to your "Baldur's Gate" folder. You can open Windows Explorer by hitting the Windows key and "E" simultaneously; the game folder should be somewhere like "C:\Program Files\Baldur's Gate."
Create a new folder called "portraits" and place it in the "Baldur's Gate" folder. Drag and drop your portrait images into this new folder.
Start "Baldur's Gate" and load the character creation screen. Click the "Custom" button by "Portrait" to load your newly created files.