In The Tempest, how does Trinculo act, and how does Shakespeare present the conflict among Stephano, Trinculo, and Caliban?

Trinculo is a cowardly, selfish fool, and his words and actions all show this. When he finds Caliban, he thinks of taking him to England to be displayed for money. Then they get drunk together—not a good action when you're stranded on an unknown island. As they do, they start to make plans to overthrow Prospero. As a rule, it's not a good plan to make political plots with someone you consider a sideshow attraction (Caliban).