First things first, make sure you have a 3D printer. If you don't, don't worry! You can buy one or ask your neighbor.
Slicing your model is like slicing a pizza, but with more layers and less cheese. Use Savant or Slice Ninja to slice your model into perfect 2D slices.
Now it's time to print your sliced model. Make sure your 3D printer is set to print mode and press Print!