How do you expose for a silhouette? It's easy. Simply point your camera at the bright light source -- in this case the sunset sky -- and shoot. No exposure compensation is needed. The bright lit area of the composition will force the meter to underexpose the subject. Hence, you'll get a silhouette.
Even though the sky was much brighter than the cheetah, the illumination was still not excessively bright. I wanted as much depth of field as I could get to show definition in the sky, and that meant that my shutter speed wasn't fast enough to prevent the blur of the cat's left front leg. I used f/16 and 1000 ISO, and the shutter ended up at 1/100th of a second. I don't mind the blurred paw because it shows motion, but the truth is that if I had a choice, I would have preferred total sharpness.