Make sure that:

• All the people onboard have life jackets.

• The wind and wave conditions do not exceed the design category of the boat.

• The dead man's switch is switched to driver. 

• There is a fire extinguisher (or several) onboard and their approval/inspection date has not expired.

• The needed ropes and anchor are onboard.

Check that:

• There is no water in the bilge.

• All the bilge pumps are functional.

• The bilge has no signs of fuel or oil leaks.

• All deck hatches are tightly closed.

Check that: 

• All the fuses are intact.

• The main switches are switched on.

• The batteries have enough power.

• The engine works properly.

• The engine cooling water flows as expected.

• The fuel level is sufficient.