In phpBB 3, you are able to give the users within a certain group a specific username color. To change or set this color, please follow these steps:
1. Access your phpBB 3 Administration Control Panel (ACP).
2. At the top, cclick on the "Users and Groups" tab.
3. On the next page, in the left menu, under "Groups," click "Manage groups."
4. You'll see a list of groups, both ones you may created and pre-defined ones, such as Administrators and Moderators. Click the "Settings" link next to the group you would like to change or set the color of.
5. Scroll down to the "Group colour" field. Here, you can enter the six digit color code of the color you want to use. You can click the "Web-safe colour swatch" link next to the text box for a pop-up window of colors, if you would like.
6. Press the "Submit" button and you're done.
I hope that this tutorial was helpful to you. If not, please feel free to ask for help in our forums. Thank you for reading.