I start with a type study to look for interesting letter pairs. Then I pick my favorites for first drafts. At this point just looking for shapes, readability and then how to incorporate a logo. All the elements are variable, so if you see something you like from the first and third ideas we just swap things around for additional iterations.
First impression would be that if this is a documented vessel the name that fits on the transom may not be large enough which drives me to consider a graphic for port and starboard sides. These can be rearranged and presented in a more square aspect ratio for use on a shirt, (as we see in #2 on the transom) but my primary focus would be the legal boat markings first and shirt design second.