A leatherworking friend once gave me some "acrylic leather finish" to change the color of shoes, jackets, etc. It smelled just like acrylic paint but was runnier.
So the next time I wanted to change the color of a leather item, I just thinned out some acrylic artists paint and it worked great!
Here's a leather coat Star
and I restyled.
We scavenged it from Mars
when he was moving.
We cut the arms off it to make it into a vest and to make leggings. Then we thinned out some "Mars Black" acrylic paint til it was watery and painted one of Star's op-amp cartoon characters on it. The paint for the golden radiance was already thin enough to use straight.
The reason for thinning the paint is if the coating is too thick it'll crack. The acrylic is very compatible with leather because it bonds well with leather, and after it dries it's porous enough to let the garment breathe.
EXTRA HANDY TRICK:
A jacket that's too small for you might fit perfectly as a vest.
All you have to do is cut the arms off it.