What you need is tanners oil or Leidreiters Leather lube .Both products are brushed on then left to soak in a few days,you may need to repeat the application a couple of times.Needs to be re-hydrated basically .
Next step is to break the hide (flesh side) ,couple of ways to do that.Over the top of a post , by rubbing with pumice.
The thicker parts round the edge will normally require more work to soften .
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