On what? an aeroplane, a car, a bus, a train?
Leather comes in all colours. Some real leather items can look very plasticky
We have to exaggerate the 'leather' look
First is surface prep. Easing the corners and edges; a bit unevenly, a few short scored lines from the corners toward the centre, The centre slightly lower than the edges
Paint; mainly a semi-matt finish overall, with sides a bit more glossy, patchy. The part of the seat & head rest, different. Seat, a lighter version of the colour for wear, in the centre towards an edge, the headrest, a slightly darker colour in the centre fading out towards the edges and a matt finish
Just some ideas