Perform an impressive dive from the cliff near the old railroad tracks.

You can grab this near the start of chapter 8. You’ll come across a small waterfall and follow the path behind it where you would usually side down a muddy slope and jump to the right to proceed with the chapter.

Instead, jump to the wall on the left and climb to the top where you can jump down into the pool below the waterfall. Chloe will perform a cannonball which will unlock the trophy.

Cannonball!

Perform an impressive dive from the cliff near the old railroad tracks