Painting Cowhide

I have a mix of leather clothing that I wear often but have no idea how to clean it properly?

Deerskin leather dyed vest.
Thick cowhide leather arm bracers with painted detail.
A shirt with leather detailing trim.
and suede pants with a grease stain.
How do I clean these items without going to a dry cleaner.

both of the other suggestions, might be able to clean leather used on car seats, or on boots, but your vest, is not made of standard skins. The piece should be cleaned at a facility that specializes in cleaning leather. Most dry cleaners do not have the ability to clean such a garment. If you do try to use an over the counter leather cleaner, test clean a very small area, to assure that the leather does not turn color, that the painted decoration does not come off. Suede is never cleaned with over the counter products. Your pieces sound expensive. Don't take a chance with methods offered by the first two responders. I guarantee you will regret doing so. Take the pieces to a professional source of leather garment care.