Hey there Art,
I'd be glad to help you explaining how I mix my paint !
So it's about the clothes you want to know :
oils I use for mustard trousers are Raw Ocre, Burnt Umber, Ultramarine Blue, Emerald Green and White.
For the shadows I add more blue and umber, for highlights on the folds I add a bit of white.
For the leather jacket : Burnt Sienna, Ultramarine Blue, Yellow Ocre, Burnt Umber, White.
For the shadows I add more ultramarine and sienna to darken, for the highlighting I add just a bit of yellow ocre and a tiny bit of white.
This is one of my cups :

It's very important to paint very thin layers of heavily diluted amounts of paint (that's my vision, there are certainly more ways to do it), ment to create many tones to make it like the real stuff. Advantage : it drys quite fast, so you can continue sooner. It will never go as fast as you would use enamels ore acrylics, but oils are so easy to blend and you can take your time, no rush against the clock (very important I think).
To find the right tones, you have to 'fiddle' until you are satisfied. I hope I explain myself ???
Oh yeah, I always start with dark tones, and finish with the brightest ones.
I hope this wil help you.
Pat : thank you for your supporting words !
Greetz Guy