The way I understand it (anybody please correct me if I'm wrong) is that you get one skill point for each weapon level you earn, and that the maximum weapon level, at this time, is 25. So you have to decide which skills (and how many) you want to put your 25 skill points on for each weapon (including sailing and cannons).
I have played the game as far as you can go in the game to date (the Boss battle), but haven't maxed each weapon yet, so maybe my info is incorrect. That's my current understanding of how it works, however Ive been known to misunderstand before...
