Best result is to replace the actual leather and cushion if they are worn. But if you don't want to spend the money, there are alternatives that look good.
I've sanded and repainted my seats (shale color) and they came out great, but it was a bit of a pain bc my Yuk is my daily driver, so I had to start the project on a friday and not drive until monday, but you should really wait longer than that so the dye cures.
Recently, I decided I wanted grey seats. I painted the rear seats and they came out nice. When it came time to do the fronts, my drivers side seat cushion was flattened a bit so the leather creased badly and I didn't feel like replacing the cushion and seat cover, and then have to paint, not use my truck.....etc. I purchased CoverKing custom fit seat covers in grey. They look great IMO and the grey almost matches my interior (can't tell unless you are actually comparing). The only part of the seats that don't fit snug is the area where the armrest folds up. CoverKing said it is normal but tried to correct this by issuing me a new backrest, which helped but still not perfect.
Hope this helps you. Another brand is Caltrend.....which might be better (they only make seat covers I believe), but I have never seen them on our trucks.