The law of fixing a nail on wall is very simple. You put a nail on wall. Then use hammer on head of nail, again and again. Gradually it fixes it’s place on wall.
Wall is another name for Resistance. When you want to change anything, you are facing resistance. A wall.
The action of change, is the nail. You have to apply force again and again till the change penatrates in the wall.
Once the nail get fixed in wall, once the change is engrafted in system, job is done.