He has gone every year for the past few years with his friends, and here is a layout I did of some pictures from a past event.
Since his costume for that year was orange and blue, I used those as my main colors. I found an image of the actual character he was dressed as online and added that, along with an image from the Anime Detour promotional paperwork he had.
Oh . . . and I made his costume too . . . yet another one of my crafty creations.