Relief sculpture is a great way to practice and fine tune your sculpting skills. Especially if you are interested in doing portrait work, this is a good starting point.
In this PDF workshop you will be following a step by step process to build the face and features. By working on a flat surface you don't have to worry about how you handle the clay as much as you would with a full 3D sculpt. A placemat template is included in your PDF file to use as a guide with this class.