In the assignment I said:

The general technique is to write a method that takes these parameters: The Graphics element on which to draw (optional--could be a global). The x, y location at which to begin drawing. Although most graphics methods (such as drawRect) use x and y as the top left corner of the thing being drawn, you will find it more convenient to use these as the center of the figure you are drawing. Some measure of the size of the drawing, such as the length of a side. A counter to control the depth of the recursion (optional--can use size instead).

Additional points:

• Be sure to use as parameters both the location (as x, y) and the size of the drawing, and don't get these confused. Size and location are independent, and must be treated as such.
• To compute a new location for the recursion, do not multiply or divide x or y by anything. Always use the current x, y location plus or minus some function of the size. (If you do a little arithmetic at different locations, you will see why this is important.)
• Use depth - 1 in each recursive call, rather than setting depth = depth - 1 before all the calls. Either way usually works, but the former is a little safer.
• Drawings with diagonal lines sometimes require a bit of trigonometry. Use or avoid, depending on your comfort level.
• If you are using integer arithmetic, remember that division isn't always exact. This will affect the smallest parts of your drawing. If it looks good, don't worry about it. If it looks bad, try tweaking your initial size.
• Avoid global variables!

These are not intended as additional requirements. If you get an interesting pattern (probably accidentally!) by violating some of these, feel free to keep it.