Like a Dragon: Ishin!

This is fairly straightforward and easy to do. Once you begin chapter 2, head to the river southeast of Teradaya Inn. There is a spot that says "River Fishing", enter the minigame there. To catch fish, select a spot to cast your line and press A. Try to place it in front of the outlines of fish in the water. Wait until one approaches it, then turns red. Wait until the controller vibrates as the red mark on your bobber enters the water, then hit A. Simply repeat this ten times until you unlock the achievement.