I think the easiest way to build a beginner ship is to just build a somewhat large rectangle, give it some depth and a deck (essentially making a rectangular prism), then have a slope going from the keel to the bow's deck. It'll look ugly but it's easy to make and gives you plenty of room to put stuff inside the boat. You're probably going to want to build it a bit bigger than you think you will have to. If you try to make the front of the ship look like an actual ship you're going to end up pulling your hair out trying to get all the slopes just right, so just go with the wedge.
Where possible try to use the 4 meter beams, since they're stronger than the equivalent amount of normal blocks, and they cost fewer computer resources to simulate.
Of course I'm not an expert myself...
Tried this game out a while ago and after doing the first tutorial(?) mission, and steaming around finding nothing, I went into sandbox to try to build a boat and couldn't figure out how to start one. Also it seems that there is a need to get resources but I never seemed to need any? And I hear people in this thread talking about AI controlled boats but I never saw any? I think I've been playing the wrong gamemode or something.
I think I'd love this game if I could actually figure out how to play it.
In addition to MrRoboto75's advice, I'm curious what method of camera movement you're using? There's a 'free' camera that operates more like Minecraft and its ilk, and there's the 'orbit' camera that orbits the piece you're going to put down. Try to get used to the orbit view if possible, and remember that the controls are always listed on the left hand side. Once you start your new vehicle it'll spawn that lone wooden block; you're going to want to add a few blocks to this otherwise it'll despawn, then just build on it from there.