Leather found at craft stores isn't high quality, rather think, and minimally treated. If you ever find it in an misbent shape or curly from being wound on a spool, fear not, it's quite easy to fix.
I purchased a spool of leather cord for some necklaces, but they came out with this intense curl which was hard to straighten.
Didn't think you can put it in hot water? Well if it's not fancy treated, you actually can. I soaked the leather in hot water, a treatment also used to soften the leather before stamping, a method I learned from some real CowBoys!
Hang to dry. But be careful of the position in which it dries, it will keep it's shape as well. My ending strands ended up with a fold in the middle, luckily I didn't mind because that's where my pendant for my necklace is going to sit anyways.
TaDa, from Curly to Straight (ish)