Measuring for a retractable RV shower door involves taking precise width and height measurements of your shower opening. Start by measuring the width at the top, middle, and bottom of the shower frame, then use the smallest measurement to ensure the door fits properly. Next, measure the height from the shower base to the top of the frame. Make sure to account for any trim or molding that might affect the fit. If any part of the instructions is unclear, focus on these key dimensions and consider sending photos or specific measurements for detailed assistance. Following these steps will help you order the correct retractable shower door size for your RV.