1) Print the Full Plate or 3x Legs, 1x Top Connector and 1x Bottom Connector. I suggest printing with 2 perimeters, 0 solid layers, .125 fill density, honeycomb fill pattern, infill every 1 layers.
2) (Optional) Super-glue the parts together - be sure to keep the top and bottom connectors in the proper orientation since the slots are angled.
3) Place (optionally super-glue) the assembled thing into a Solo cup. I chose to glue it because it makes it completely sturdy.
4) Place the avocado pit in the thing pointy-side-up.
5) Fill with water to about half-way up the pit.
6) Place on a sunny windowsill and wait a few weeks. The pit should split at the top.
7) See here for more information: thehungrymouse.com/2009/09/09/how-to-grow-an-avocado-tree-from-an-avocado-pit/
8) Keep the cup so you can reuse it next time you crack open an avocado!