Boat shaped mold (I used a Tupperware bowl but almost anything can be used)
Bucket to mix concrete in
First create a mold of the shaped boat you want. My mold was a medium sized plastic Tupperware bowl, but you could create one out of wood, Styrofoam or anything else.
Coat the mold with silicone spray so that the concrete will not stick to it.
Put the concrete in the bowl and smooth it out with your hands until it is distributed evenly.
Let the concrete dry for at least 24 hours and then remove it from the mold. Now let it float! (:
Mix the appropriate amount of concrete and water together, make sure to wear rubber gloves!