I first sprayed the deer head with primer so everything would stick and not chip off. After that, I painted one coat of Modern Master's Crackle for Latex Paint. When that dried (about 20 minutes) I took a tiny trowel, you can use an icing knife if you have one, and started slapping paint on!
Literally, I just apply it randomly using different directions and motions. Then, I applied another coat of Modern Master's Crackle Medium. I took a different color of paint, and slapped on another coat! I repeated these steps with three more colors of paint. I used Tyler Taupe by Benjamin Moore, Rattan by Benjamin Moore, and Cork Wedge by Sherwin Williams. These are all coordinating colors that I had laying around. After that dried, I decided to glue on some acrylic jewels to make it look like nail heads around the border of the statue. I painted over those jewels around the border with Pale Gold by Modern Master's.
After that dried, I applied Annie Sloan Dark Wax. When I brushed this on, it stuck in the cracks and crevices for low lights and highlights. Voila, aged "plaster".
If you have something you have given up on, try to salvage it by updating the look. I bet you would be surprised!!!
Have a lovely day!