Press the green flag to start drawing. Tell the bug how many steps it can move to set the max step size. Use up, down, left, and right arrows to move the bug around to draw. Once your done or if you mess up just press space bar to clear the drawing and snap back to center.
At the top of the page you can see the newly added stepsTaken and stepsAllowed. The first one shows how many steps the bug has taken. The second one shows the max step size you allowed the bug to take.