I always thought this is tricky but not at all :D
Score at 5.5" (this is the middle fold) and at 2 3/4", that becomes the front wedge.
From the picture you can see that the front image was glued over the bottom half of the wedge.
The sentiment was used as the 'stopper' and you can gauge how wide you want this.
Cardstock for base: BasicGrey
Boat stamp and sentiment from GinaK Design, "Enjoy the Sunshine"