Final answer:
The first major decision after drawing the first circle in an Islamic geometric pattern is determining the number of equal sections for division to ensure symmetry and repetitive patterns.
Step-by-step explanation:
After drawing the first circle in an Islamic geometric pattern, the first major decision you take is into how many equal sections the circle should be divided. This is a crucial step as it determines the pattern's symmetry and repetitive nature, which is an essential characteristic of Islamic art and specifically geometric patterns. The divisions within the circle set the framework for constructing complex geometric shapes like stars and polygons that can be repeated endlessly throughout the design.