Start by creating the mushroom stems. To do so, decide how many mushrooms you'd like to make, then roll out long cylinders of clay, making one for each mushroom. Use your paintbrush to add some water onto the clay to help prevent cracking.
Now get a piece of wire. Measure it to be slightly longer than your stem piece. Then, starting at the bottom of the stem, slowly thread it through the entire piece.
Next, make the mushroom caps. Roll out a ball of clay for each mushroom. Then press your thumb into the ball to create a bowl-like shape.
Use the wire to create crosshatch marks on the inside of the cap piece and the top of the stem piece where the two pieces will meet. Then dab a little water onto each piece and press them together.
Let the mushroom dry according to the manufacturer's instructions. Once it is fully dry, paint the mushroom (if you'd like). Then, allow the paint to dry and apply an acrylic sealer. Let dry fully before adding to your terrarium!