The key tools are actually sharp, flaky, uneven stones and blades, other tools may apply for more details. You may want to practice a little before you work on your projects. Well, it supposes to be fun, so relax and let go with the clay. You may add an armature first if you need, especially a bigger trunk. Please advice if you have any suggestion or question. Part 2, 3 or maybe... are probably wood board, pile wood or rotten wood etc.