Thanks for the comments guys

For the leather I have used a mixture of acrylics and oil paints
The base color is a mixture of Vallejo 822 (German Camo black) + a little bit of Vallejo light skin color.
for the lighter upper part I've used the base mixture + a little bit of Life Color light stock wood and Vallejo light orange and I have applied the paint in very thin washes working for the inside towards the outside of the coaming.
to paint the shadows (here the lower part of the coaming) I use very thin filters of Vallejo 822 + little bit of Vallejo black, progressively making it darker towards the lowest part.
Afterwards I've applied some thin filters of Burnt sienna oil paint.
It's a fairly easy technique, but it takes some time to do. Try it, you'll like it :-)
The seat cushion was done in the same fashion.
All the best
Flip