Use a toilet auger not a regular drain snake to avoid scratching porcelain. Insert the auger cable into the bowl opening and crank the handle clockwise pushing the cable through the trapway. When you feel resistance continue cranking to break through the clog. Pull the cable back slowly removing any debris caught on the end. Flush to test drainage. A standard toilet auger reaches 3 to 6 feet into the drain line. For deeper clogs a professional motorized snake is needed.