Once the resin is completely cured, use your fingers to push in the middle of the mold to release it. Basically, at this point, your cabs are finished the "resin" phase of the process. However, you may notice the edges of the cabs will be a little rough. You can clean them up using a craft knife to trim up the edges as well as a little fine sand paper to smooth these areas.
As you can see, most of the supplies I purchased at a craft store or used disposable items (like spoons and cups) that you can buy at a grocery store, so you don't need a lot of specialized equipment to work with resin. Of course, make sure you read and follow all manufacturers' safety guidelines when working with resin. It's important to be safe while you are having fun.