Gather the number of Styrofoam balls needed to represent the atomic particle. For example, grab three balls for a single molecule of H2O, two for hydrogen and one for oxygen.
Write the symbol for the atom on each ball. For example, write "H" for hydrogen.
Hold the ball in one hand, a pencil in the other, and then drive the pencil directly toward the center of the Styrofoam ball.
Look at the picture to reference the atomic element attached to the last ball. Label it and then attach it by sticking it on the other end of the pencil. This is an atomic bond.
Continue building your atomic bonds by repeating Steps 2 through 4 until your model is complete. Use care to arrange the atoms in the same orientation as the picture depicts. Remove the pencil from the Styrofoam and adjust the angle of insertion if necessary. Mistakes are masked with paint later.
Paint the atoms using the color scheme from your picture using a filbert brush. Use a different color for each atomic particle. Allow the paint to dry before finishing.
Write the atomic symbol on the colored spheres with a marker. For example, write "H" on the hydrogen atoms in a water molecule model.