Choosing the right size life jacket is crucial for both comfort and effectiveness. Sizes are typically based on weight ranges and chest measurements. It's essential to try on the jacket and adjust the straps to ensure a snug fit without being restrictive. A properly fitted life jacket should not ride up excessively when pulled upwards by the shoulders. Adjustable straps at the sides, shoulders, and waist help customize the fit to your body shape, ensuring comfort and safety.