In this photo, I used a cheetah face, and my own eyes. For my neck, I copied the cheetah face, made another layer, erased everything except for the forehead, and fit it to my neck. I cropped this photo so I would be off to the right instead of being centered. I like how this one turned out because the gradient background and my hair colour match the cheetah fur colour well.
For this photo, I used the face of a gorilla, and my own eyes. I cropped this picture, similarly to the cheetah photo above, except I also cropped it so there wouldn't be as much background above my head. A challenge with this photo was getting the animal's face to fit mine, and it did not end up working so, I copied the face twice, and made two new layers, one for my neck, and one for my forehead. From the copied face layers, I erased everything except for the forehead, and used that on my forehead and neck. I don't like how the forehead looks in this picture because the forehead layer is overlapping with the face layer. On the neckline, it also overlaps, but I like how it looks there because it simply looks like collar bones, not a poorly done neck.