Instructions
Log in to your "PSOBB" account. Take your character to the Information Counter. Select "Team" and "Create Team" from the menu to create your team along with your default avatar. Log out of and shut down "PSOBB."
Click "Start" and "Computer." Double-click the "C:" drive and "Program Files" or "Program Files (x86)" if you have a 64-bit operating system. Double-click "Scheserv PsoBB" and then "Team Flag." Rename the image you want to use as "Flag.bmp." Drag and drop "Flag.bmp" into the "Team Flag" folder.
Open and log in to "PSOBB." The team flag will show the image you just saved into the "Team Flag" folder. "PSOBB" will automatically resize the image for you to make it fit.