Bart Simpson looks like he is deep in thought as he stands in front of the tree. He has his hands in his pockets and his face shows a hint of mischief. His bright yellow, spiky hair contrasts against his bright red t-shirt and blue jeans. You can almost see a mischievous smile as he looks off in the distance. To emphasize his spiky hair, you could use a lighter shade of yellow for the tips of the hair. His red t-shirt could be colored a brighter red, while his jeans could use a lighter shade of blue to bring more attention to them. The tree in the background could be colored an earthy brown, while the detail in the leaves could be colored a vivid green. The colors used will all depend on what type of mood you want the picture to portray.