Create a wire frame for the tree's trunk and thickest branches. Twist together the pieces of wire by bundling them together, then gripping them at one end with a pair of needle-nosed pliers. Twist half the length of the wire bundle tightly together, then pull the remaining lengths of wire away from each other, bending them about to form tree branches.
Insert the bottom end of the wire tree trunk into a balled-up lump of aluminum foil. This will create a prop that you can bake after sculpting the rest of the tree.
Sculpt the leaves. Coat each of the wire branches with a roughly cylindrical clump of green polymer clay. Use a craft knife to slice at the clay coating, pulling away small sections of it. Flatten these sections by pinching them in order to form leaves.
Create the flowers. Roll a piece of yellow or pink clay into a cylinder whose cross sections are roughly 1/3rd of an inch in diameter. Stick the roll in the freezer for a few minutes to stiffen it, then cut thin cross sections using a straight razor. Pinch each cross section to flatten it a little. Form each flattened piece into a flower bud by pressing a toothpick into its center (making it conical), then indenting the edges with the tip of a needle to form the petals.
Attach the leaves and flowers to the frame. Press each bud onto part of the greenery by positioning the toothpick or needle in its center.
Bake the model according to the instructions on the polymer clay package.
Position the tiny tree inside a small ceramic flower pot. Fill the pot with brown polymer clay, then poke the bottom end of the tree trunk into the clay.