How to pick a boat? Ishmael doesn't know, but Queequeg, based on the advice of his idol doll, insists that Ishmael picks the ship that they will spend the next 3 years on. Ishmael has never been whaling, so he has no frame of reference for what makes a good boat. We are all going through life blind. What we each are going through, nobody has ever experienced. There is no precedent for anything. The cosmic implications of this are unfathomable. It makes you question time and its existence.
With no other criteria to fall back on, Ishmael picks the boat that strikes him the most in an aesthetic sense.
...you never saw such a rare old craft as this same rare old Pequod. She was a ship of the old school, rather small if anything; with an old-fashioned claw-footed look about her. Long seasoned and weather-stained in the typhoons and calms of all four oceans, her old hull's complexion was darkened like a French grenadier's, who has alike fought in Egypt and Siberia. Her venerable bows look bearded. Her masts--cut somewhere on the coast of Japan, where her original ones were lost overboard in a gale--her masts stood stiffly up like the spines of the three old kings of Cologne.
We are each of us at all times in search of our own ship that will take us on our journeys with no idea which is the correct to choose. Ishmael chose the Pequod out of three possible boats. The other boats are not described because the Pequod struck him so. We are often blinded by beauty or that thing which we seek with bias. Our aesthetic sense could lead us to our doom should we ignore other signs.
The choices we make are the vessels that carry us through this sea voyage called life. Our careers, our friends, our mates. How do we choose these things? We have no frame of reference to make an informed decision for these things. We are all doing it for the very first time in our experience and in a metaphysical sense. We often make decisions based on gut reactions, but our guts often leads us wrong. The best we can do is pick and hang on for the ride.