Engine and fuel

• Service the engine: Change the engine oil and filter to remove contaminants.
• Stabilise fuel: Fill the fuel tank to prevent condensation and add a fuel stabilizer before running the engine for a few minutes to circulate it.
• Winterise cooling systems: Drain all raw-water cooling systems. For closed-circuit systems, add antifreeze. 

Electrical systems

• Remove batteries: Disconnect and remove all batteries, clean the terminals, and store them in a cool, dry place. Charge them occasionally or use a trickle charger.
• Inspect and protect: Check for corrosion on terminals and connectors. Consider spraying behind electronics with a water-repellent silicone spray. 

Interior and damp prevention

• Clean and empty: Remove all food, linen, clothing, lifejackets and other items that could be damaged or attract pests.
• Ensure ventilation: Leave cupboards, lockers, and drawers open. Prop up bunk cushions to allow air circulation.
• Use moisture traps: Place moisture absorbers or traps in small areas like lockers to combat dampness.
• Manage water systems: Drain all freshwater tanks and lines completely. If recommended by the manufacturer, add a non-toxic antifreeze to the water system and toilet system. 

Exterior protection

Check for leaks: Before winterising, inspect the boat for any leaks and make necessary repairs. 

Cover the boat: Use a high-quality, waterproof cover that fits snugly to protect against snow, ice, and debris. A custom-fitted cover or a frame to prevent sagging is recommended.

Remove and store: Take off sails, covers, and sprayhoods if possible. Wash and dry them thoroughly before storing them ashore to prevent mildew.

Secure items: Check that all deck items are secure and serviceable.