You are applying amrut malam which is good...
Whenever you enter home wash your feet with lukewarm water for 2 to 3 minutes
when you go to sleep again wash your feet and apply caster oil directly or mix castor oil with glycerin in night.
Next Steps
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Health Tips
At night take milk with 2 teaspoon ghee.
if he work in soil ask him to cover his feet,
He should always put on shoes.