Took my brand new Orcas and put them through hell. I started by scrubbing them with steel wool to dull up the patina. Once they were sufficiently roughed up, I coated them with wood putty.
I let them sit for 8 hours and then I scrub off the excess, ensuring that each crack, crevice, and seam retains a good amount of dry wood putty.
I then coat the boots with black grease. Make sure it has a high viscosity so it goes on thick.
Let it dry for about an hour then scrub the boots down.
Repeat as many times as you want until you get the desired look.
For the soles i mixed some beige oil-based paint with mineral spirits, about 60/40 and brushed on the slurry in the areas I wanted to touch up.