MyBB Community Forums

On my old forum i had these type of banners but i can remember how i did it does anyone know? I learned from a thread on here but i cant find it.

1) You can create a banner with Photoshop or Get a banner from here Link
2)  upload it to imgur.com-> open image in new tab-> copy the link it should end with .gif/.png
3) Go to The ACP > Users & Groups > Groups > select the Group Name > Paste the Link to Group Image Field