The mink oil is a soft thick waxy substance that is best rubbed on with a cloth.
To really soften up new leather I really plaster the leather with mink oil. and allow it to soak in over night before working the remaining oil into the leather.
The best way to do this is to melt the mink oil until it is runny and just daub it on with a piece of rag or a sponge.
Rub the warm oil into all the seams and joints and around any of the tough areas that are prone to causing blisters mainly the tough seam at the heel.
Apply a really thick layer of mink oil until the whole boot is totally covered, I then like to use a heat gun or hair drier to melt the mink oil on the boots until it turns liquid, this heating will open the pores in the leather and help the mink oil to soak in even more.