Defeat or capture leather-dropping Pals such as Lamball, Cattiva, Foxparks, Direhowl, Rushoar, and Melpaca
Loot leather from defeated Pals on the ground
Buy leather from merchants in settlements
Check dungeon chests and other loot containers for leather
Use a Pal with the right combat strength to farm leather efficiently
Repeatedly hunt leather-dropping Pals in their usual spawn areas