What you wear for cold water paddling will vary depending on the water temperature, weather and the wind, but the same theory applies for any temperature.
To keep warm your skin must be dry. The first layer is used to move the moisture away from your skin and into the outer layers. The shell is used to keep you and your insulation dry. Most insulation works much better when dry.
Dress light. As you stand on the shore before going out you should feel cool. As you start paddling you will warm up quickly. Adjust you temperature by adjusting your head gear and gloves. You can also put a wind breaker/Storm Cag over your dry suit.
Following is a list of clothing. It is listed in order from against your skin to the outer layer. The middle layers are used to adjust for different temperatures.