I NEED HELP WITH SYLESTIA

How do you catch a wild animal?

You should be able to buy traps from Esior's Haven Market (Lesser Snare Trap), Sanctuary of Saerielle's Market (Standard and Lesser Snare Traps) and Ethernia's Market (Strong, Standard and Lesser Snare Traps) you can then use traps when you're in combat with a Sylesti by selecting the Inventory, choosing the trap you want to use, and then selecting the Sylesti you want to capture.

If you're in Sweet Blossom Orchard or in one of the Festival Zones then you click on the Manage Button, then the Traps Button and then selecting the trap you want to use and the Sylesti you want to capture.

I think that at the beginning of the game there is a quest to capture a Sylesti, but in that case it's automatic and an event should pop up as you explore.

Hope this helps! ^.^