After acquiring the Light Shoes (and Crystal Ring to speed up the process), go to the Casino area and step on the button to make the rings appear. Do this by repeatedly for more starting rings. Note: The ring limit can exceed 999, but you cannot tell exactly how many you have. Listen for the extra life sound to keep track of them. When satisfied, go to Emerald Coast and complete the level without getting hit. You will be awarded with the rings you collected at the end. Go to the Chao Garden, then the Black Market, and spend your hard earned coins.