You've got the rod, you've got the bait - fishing time!
You can change your line's colour by using the top set of arrows, and change your bait by using the bottom set of arrows.
This is the low-spoiler guide for "How to Fish" puzzle in Cleo - A Pirate's Tale. Unlike in normal walkthrough, you get gradual hints on how to solve the puzzle. Click the big button below to see your first hint. If the hint contains a spoiler, you will be warned about it before clicking.