This method was first introduced to me by my junior high school art teacher. Since then, I have used it several times with fantastic results. Not only is it much cheaper than sculpting with metal, it is also easy enough for younger artists to do without much difficulty.
Step 1: Make Your Clay Figurine
The first step is to make the figure you want to look bronze out of clay. Since this was a birthday present for my brother, I decided to make a figurine based off of the statue of the Army mascot, Hannibal the mule. I used white Sculpey brand clay, which needs to bake to harden. I used an armature of tin foil and wire clothes hanger parts so that I used a little less clay and gained structural support. Before the next step, be sure to bake your figurine according to the product's instructions, and allow time to cool completely.
Step 2: Heavy Metal, Baby
Paint your cooled figurine with the metallic paint. Choose your acrylic paint based on what kind of metal statue you want. I used metallic copper. From experience, I know that copper or bronze makes a very realistic statue, while gold or silver is slightly less so. If you do decide to use gold or silver, I may suggest skipping the next step, which is blackening, or at least using less black. You may decide to skip the next step, anyway, if you feel that you are satisfied with your figurine after the metallic paint. Allow the paint to dry thoroughly before the next step.
Step 3: I See a Bronze Mule and I Want It Painted Black
This step is what I personally feel makes the statue realistic. If you have noticed, most outdoor statues are not that shiny, and many become dark over time. This is due to the effects and elements of nature, such as oxidation, corrosion, dirt, and grime. Most people are aware that even the statue of liberty was not originally that pale green color.
To add this touch to your figurine, start painting it with black acrylic paint, using a slightly larger brush. The idea is not to make it solid black, but to let some of the metallic paint shine through underneath. To accomplish this, you can use a paper towel to smudge the paint on your figurine, making it look dirty. Experiment with how dark you want to make it look. Allow to dry.
Step 4: Mmm, Glazed Mule
Use a clear, brush-on glaze to finish your figurine and give it a final shine. I used a Sculpey brand purposely made for their clay. Use two coats if desired, allowing to dry in between.
If you want, after the glaze dries is the time when any accessories can be added, such as reins made from embroidery floss.
Enjoy your clay statue!